Are there any real concrete ideas to fix the VA?

You have touched upon one of the reasons that I have long advocated that veteran healthcare be administered by the military. They have an established system that, at least by my experience, works well. Much of it sits idle being built for war time service. Treating veterans would spread the investment and "exercise" the system during peace time. During periods of war, ambulatory veterans could provide comfort and solace to patients arriving from the battlefield. I can think of many other reasons and I bet you can too

I'd rather pay than go to the VA.

This seems to be the million dollar (literally) question. I'm retired so can still use the military medical system, which I do. We are fortunate enough to live close enough to a base that we still use the base clinic as our PCM. I have never been disappointed with the quality or timeliness of the care we receive. We also have retired friends who use local doctors rather than the base for their care and they also say they have no problems with the military medical system relationship with their providers.
Then there is the VA system which seems to be like night and day compared to the military system. When I was working I has several vets who worked for an with me who used one of the two VA clinics in the area. The stories I heard about trying to get appointments and frequently the quality of care once they were seen were true horror stories. It's amazing that two medical systems run by the same government can be so different.
Health care in general in the U.S. is amazingly complex, however IMO the military medical system and the civilian medical system seem to be pretty much coordinated. In fact we are often sent to civilian doctors by the base clinic. The VA system, however, seems to be totally out of whack with the model used in both the military & civilian world. From my observations their attitude seems to be, we are the VA and we are going to do it our way.
The VA system doesn't seem to work, but the military system does and they are both part of the federal government, so there is no need to reinvent the wheel. I have no idea how to accomplish it, but it seems to me that there needs to be some directives from above the VA chain of command that forces them to bypass their entrenched bureaucracy and conduct healthcare more in-line with the military system and in cooperation with civilian healthcare.