Welcome to the forum.
Your treating trt like cycling. If your going to blast year long your asking for trouble. My opinion and probably many others.
200 gets most men into the high normal or above ranges in free t. Anything beyond that is way higher. Hematocrit, rbc, estrogen, blood pressure, prostate and other issues probably arise. What about receptors. do they desensitize? Do they get fatigue and stop working if you stay on a huge dose? Over use of anything is bad juju in my opinion. What about your liver , kidneys, skin, brain, seratonin, dopamine and host of other aspects effected by t on the body. How does the thyroid react to higher doses for years at a time. All questions to answer.
Someone else can probably elaborate on what a high dose would do over many years better than I could. I’m sure they will. But these are all questions that come to mind when I think of long term use of 350mg. I know it’s not 1000 like they would to cycle, but it is twice what most folks are prescribed.
You need to research trt much more thoroughly. It sounds like your reading about T on body building type websites and folks other than docs and professionals. I suggest looking into the therapy aspect and understanding the holes in your plan (dr crissler, dr Nichols, Nelson Virgil, dr rouzier).
If your going to blast and come off every few years, then I would think your going to suffer bad my man. Bodies not made to work like this. Commit or do not do that to yourself.
When doing trt properly and with therapeutical doses your looking at a marathon not a sprint. You will benefit across the board from cardiovascular to mental and everything else.
I hope that helps point you in the right direction!