I'm considering switching from 35N to 35P or 35M because I am wanting to attend DLI for CM. Advice?

When you get to Monterey - study hard and enjoy the training. Korea, NSAH and/or Meade should be in your future if you are a 35P, unless you have a penchant for parachutes. Stay disciplined and maintain your DLPT scores, and keep track of your hearing records.

I don't know what a 700 unit is, I can only tell you that if you are Regular Army, you will PCS to DLI and then go TDY Enroute to your next unit which will definitely not be your current unit.

Those MOS's are used in every BCT of every division, in FORSCOM, INSCOM, and USASOC. You'll be assigned to the one that has a requisition with a report date 30-60 days after your graduation date. Hope that narrows it down for you. If you want to control where you go next you have to reenlist for a duty station of choice then you'll be able to choose where you go.

Depending on the language you request you'll need up to a 110 DLAB

Ahh ... the "700 Club" brings back memories (used to be a desk officer for those guys back in my days at INSCOM headquarters).

If you go 35M, your chances of being in the 700 Club are close to zero. They have a couple, but you're going to end up in more "deployable" units or at the echelons above reality units like the 902d.

35P can be thought of as a 35N with a language. As such, you're a SIGINT wonk that focuses on translating your learned language. 35Ps are very "700 Club friendly".

Regarding "where will I end up", Operation Military Kids of all sites gives a great run-down of the MOS and where they could be stationed. Check it out.

https://www.operationmilitarykids.org/army-human-intelligence-collector-mos-35m/
https://www.operationmilitarykids.org/army-cryptologic-linguist-mos-35p/

I was a 97 E... for Chinese Mandarin. I did well with language training. I am not sure what 97 E is called now. My orders had me going to 1SFG at Ft. Lewis...I was pretty excited to get such a cool position.
Sadly, after I had finally arrived, somehow my orders were changed to a unit with a world mission of area beautification and policing the battalion area. I was the only Chinese linguist amongst the Korean linguists in the unit. There was a Tagalog linguist, some Japanese linguists, and so many people were trying to transfer out of the unit. Language school was great! Even Interrogator school was great! I heard the unit I was in is no longer active, so you will not be assigned to them. :)
<<EDIT>> In addition, while I was in the unit from heck, I spent 6 mos TDY at one of the most popular workout centers, in civilian clothes...practicing my Chinese writing for lack of things to do...there was a group comprised of 1SFG members who came in and saw me practicing my Chinese. They said, "Too bad you're not in the Army because we could use someone with that skill" I told them my unit and they were unhappy because they had requested good Chinese linguists earlier that year from my brigade to which the reply was, there were no Chinese linguists in the entire brigade. I was a 3/3/2+ for Mandarin, and untested for Cantonese.

DLI is terrific (or was, I was there 30 plus years ago!) As a linguist I would do something more in line with Civic affairs or interrogation. Crypto Linguist is not going to be as interesting IMO as your current analyst job. If you do go down that road I agree with CSM you will likely have hearing issues later. If you really want to deploy go Airborne. You'll do your time in the 82nd and you will deploy and likely combat deploy.

No one wants to spend the money to give someone a TS/SCI only to have them be a janitor.

At worst, you will probably be recycled to be a 35F if you wash out of language school.

Former 35F myself. What I saw is the intel MOS's played musical chairs with those that washed out of their original intel MOS.

I think there is probably a bias toward "technical" intel MOS's in the civilian sector more so than language or interrogation ones. GEOINT and CYBER probably being the choice pathways.