Should infantry training be used for basic training?

To answer your primary question, it would be prohibitively expensive for the Army. If all the basic training's are lengthened by 2 months, there would be less basic training Cycles per year. That means the army would have to recruit less people per year, or build more basic training facilities and allocate more drill sergeants away from combat units.
The Marines are capable of training everyone as Infantry because they are significantly smaller. The Army recruits almost half the size of the Marine Corps every year.

As for the second part of your post, if you thought it was easy, continue pushing on. I thought basic was easy and I went to airborne school. I thought airborne school was hard so I went to RIP and Ranger School. They were hard, but I passed. Every time I passed something I found something harder to do. The Army is a very scalable place in terms of effort level. You can always find someplace where it's easier and someplace where it's harder. There are units where a 180 APFT is perfectly acceptable, and there are units where a 350 is the normal squad average. It's up to you to accept the challenge. Are you the kind of person who runs at the front of the slow group so you feel strong, or the kind of person who runs at the back of the fastest group so you can get stronger?
You're not infantry first, don't ever kid yourself. I started out in the 75th, and earned my ranger tab, and served many infantry roles in training and deployment. I was eligible to switch my MOS to 11B by having my tab. At no point would I say that I am basically infantry, or infantry first. What you think is infantry, is just basic soldier skills. Infantry isn't a skill set, if it was, those chubby airsoft guys would be infantry. It's an entire culture and society.
If you like working with the infantry, and would like to do infantry things while keeping your MOS, I suggest you volunteer for RASP. It's a good challenge and you'll get to do fun things. If you decide the infantry life is for you, you can switch your MOS after you get your tab.

I can agree with you with a couple of additional thoughts on it.

I notice discipline is greater lacking the last 3-4 years with new soldiers coming in.
- That could be from Basic not being long enough, lack of discipline instilled in basic, etc.

However, our DS's have their hands tied with being "correct, nice, etc" i have told people stories from my basic who went through even 1-2 years later and they were shocked that we did "naked shower drills" got smoked for hours, called names etc. Cause even their (as they described) were "tough" but wasn't per say mean and scary tough.

It also depends on who the DS's are and their background. My platoons two DS's were both infantry, and even told us "we don't care about drill and ceremony, we are going to teach you how to clear a room and proper troop movement."
- I love that we had that extra time learning as you say the primary role of the Soldiers.

I believe to "fix" the lack of soldiering skills and discipline (which is my biggest issue) we need need to first and foremost give our DS's their power back, and maybe also extend basic 1-2 weeks.

Disclaimer: Soldier tasks and skills are at the individual and unit level when new soldiers get to their units. They "should" be practicing and refreshing on those things, however I have seen that that isn't the case usually.

I'd be for it for several reasons, but agree with WO1 (Join to see) -the first step would be rolling back years of "tying" DS's "hands behind their backs" in the interest of being more "enlightened". Personally, I think it would help the morale, effectiveness, and overall efficiency of al the services if we started with a uniform basic training syllabus. Does a Sailor headed for Deck Division need to be able to accurately operate an M4 while using night vision? It couldn't hurt. Does a future Air Force pilot need to be able to do the "slide for life"? Might make a big difference if said officer ever found themselves down behind enemy lines. It would likely help us build bonds of cross-cooperation if from E-1 to flag rank, everyone had spent at least some time doing the same things...and would logically instill a greater sense of the warrior ethic into each of us. The challenges are of course real; it would take more time, more money, and since not everyone is cut out for everything...would probably impact manning requirements. Ultimately, I think we're actually going to see moves in this direction-the Military can be slow to react to things, but it seems to be universally recognized that we need to build a more cohesive set of skills if we're to maintain our presence.

You should have joined the Marine Corp. Semper Fi.

The Marines already do this; however, they have a different mission from the Army and are much smaller. If you wanted to be Infantry first in the Army then you should have enlisted for the Infantry. Truth is you are Automated Hand Receipt first (I am guessing you spend at least 90 percent of your duty day performing these tasks) and Infantry if the situation requires. For that reason basic is intended to give you an introduction to some basic soldiering skills which you permanent party Command can build upon through field exercises and other training events. Additionally, there are resourcing issues. OSUT works for the infantry because they do not have an AIT. If we extended basic training, not only would we lose every non-Infantry Soldier in the Army for the additional time, we would have to double the number of Drill Sergeants since your Drill Sergeant would not be available to take the next group arriving behind you and we would need to increase both barracks space and training resources for what would amount to a secondary MOS.

Not to make light of what you'd said, and I do understand, certainly, why you said it...I just know I'd found both Army ROTC and USAF OTS rough enough, God knows...then again, I suppose that was me, obv, but then again, what do I know, ya know? God knows, that I got done with both was clearly a major gift from God, I guess, in retrospect, being completely honest about it...and God knows, I worked hard enough just trying to get both of those done...after the ROTC, I had to go through USAF OTS twice just to be allowed to finish...I finally passed my 2-mi run in ROTC by a few seconds on the parade-ground track at Ft. Hamilton in Brooklyn (I honestly thought the faculty were gonna faint, one actually ran with me, an APMS, an O-4, he honestly couldn't believe it, that was a REALLY good day, God's truth)...then I sprained an ankle, my run time went back up, and they dropped me...being a glutton for punishment, and the ultimate masochist, I suppose, I did the USAF OTS thing, and passed their 1-1/2-mi run by literally one second, being paced all the way by one of my roommates from the first class I'd been in, before, just I got recycled (one guy had been an NCAA track star, the only time I ever saw one up close...he did the mile and a half in 6 mins, I kid thee all not, hopping like some sort of weird gazelle or something, totally blew my mind, honest)...then, I nearly broke my neck getting to the top of the dreaded tower climb on the Lackland obstacle course, aside from all the rappelling, orienteering, and obstacle-course stuff I'd done before with my ROTC unit (which no longer exists now) up at West Point, we trained there quite a lot...so, honest, if you found your Army basic easy, more power to you, God knows, that's all I can say, God's truth, guy...the one thing that totally stunk when I was at Lackland for the USAF OTS was that we got to do only the obstacle course, not the firing range (back then, we were supposed to have been allowed to practice with .38 pistols, we'd been told, though I had done some M-16 stuff with the ROTC unit before, at Ft. Dix before that, thank God, and also some more M-16 stuff up at West Point), for what I'd found a genuinely weirdly amusing reason at the time, though we were all obv grumbling about it...the ammo was apparently too expensive to waste, if you can believe it...and yeah, that's a true story, swear to God, guys....

That's not a bad idea.

Because being infantry isn't just a 14 week course and you're done with it. It's a lifestyle for however long your contract is. You live with misery 24/7/365, not just 14 weeks. Arty (you mentioned battery so I'm just guessing here) is usually nowhere near direct fighting so they never develop the field craft skills needed, they don't need to. Arty doesn't hump anything anywhere, the infantry...at least light infantry...that's all they do. Yeah, other MOS's get taught how to shoot a rifle and the very basics of infantry skill sets, but make no mistake about it, you're not infantry or even "basically infantry". You're a basic soldier.

I guess I can finally say the “ Back in my Day”. I agree that BCT/ AIT needs to bring back attention to detail and discipline. The DS should be the ones to strike fear in to these new recruits. By the numbers and smoked until it’s done right. Get rid of the political correctness, cell phones, Pvt’s have feelings, stress cards, individualism. Bring back polished boots, wood line counseling, forced hydration, lines for the pay phone. Line units should toe the line as well. Limit the death by power points, let NCO’s be NCO’s. Keep the military bearing and instill morals up and down the ranks. If there’s not a compliance, hit em were it counts. In their pay check! But it all starts at BCT.