I would go ahead and run the gram a week of test if I was you. I did it before and made great gains. I also ran 600mgs/wk of NPP and jump started with Beastdrol the first four weeks. Could I have made the same gains off of 750mgs test a week? Probably, but like you I wanted to experiment and get it out of my system. So just do it. Train hard and eat like a beast.
Sides experianced from this cycle vs. a lesser test cycle zero differance. Didn't notice anymore water retention, zits, gyno, and I'm still alive.
I probably won't do it again, because I realize that it's food and training that probably made a bigger differance in my weight gain than the extra 250mgs of test.
I think the real magic happens when you bump your test to 2,000mgs/week or more. I will never be brave enough to try it, so I will never know.
It truly is genetics, Diet, and training that make you look like what you look like, gear adds an extra 20% or so in my opinion, maybe a little more for some and a little less for others.
upping the dosage means you have to up everything else. you have to have the right balance of everything involved. so if you up your gear and not food, training, water, rest ect. you will get verry little in the way of added gains. what you will always get is more risk of death.
now if you take a bigger dose of gear and add everything else accordingly you will see the added results and again the greater risk of death and all other less serous sides.