There something that I believe some people do not understand about TRT. It is meant to restore NORMAL testosterone value, that's it! It is not meant to induce supraphysiological value at which you can gain more than you will at normal levels. So, if one was making poor or no gains while they were hypogonadal and untreated, they will likely see an optimization of gains, but not extraordinary gains that one will experience at supranormal levels. So when treated with TRT, aside from genetics and proper nutrition and training, a T-treated will just function like a normal, healthy guy.
Most ordinary guys, if they do everything right, will likely experience a fifteen to 20 pound muscle gain the first year. Some bodybuilding and nutrition nerds who have thought this over more than I care to, have said that one can see a 25 pound muscular gain in a year, but this is extraordinary, I believe. With each passing year, the gains become slower and slower.
Two hundred mg per week is twice the starting dose for TRT with injections. Did your doctor prescribe this amount? I would steer clear of a doc who starts one out at this dose.
A diet of 1500 kcal diet is a semi-starvation diet, is not healthy, especially for someone in your situation, who has quite a bit of education on his hands, and is likely necessary only for contest prep bodybuilders at the last legs of prep who for some reason botched things so badly that they need to starve themselves to get ready, not some guy who wants to just change his body.
Eating "clean" is not necessary all the time provided one knows what they're doing with total caloric and protein amount and getting enough micronutrients. Supplements are not necessary, but can help for some. I personally can't stand protein powders, but I do have Plazma or Finibars peri-workout.