Weeks 1-12 on 750mg Test E might be a little much
Weeks 1-2 it'd be good to use 750mg of Test a week but after that I'd drop the dose down a little bit and let the tren do the work for ya. But not much lower, never lower than your tren, maybe drop it to 500-600mg per week (someone else can help me out here with the dosing)
Everything else looks pretty good to me. I like the exemstane. What's your PCT looking like? Did you get any Tren-side affect drugs, like caber? (I believe that's what it's called). It can help with Tren dick if you get it.
You get bloods done?
And 15-20% BF might be a little high to run this cycle, are you trying to cut?
If you're trying to cut I would just use 250mg of test e week for 10 weeks and hone in on your diet. That'd be much better and less hazardous than a full blown experienced tren cycle. But yeah I'd save the tren for a bulk cycle when you're at a lower BF%