i have short but big strong legs and its harder to sink the triangle on other heavy weight really need to angle my body right and i stopped bulking up just so i am not as big is that smart

you dont need to make a triangle... you can still choke if you just squeez and bring down the head... the triangle is just to keep leverage but its not 100 percent needed

In the grappling subforum there is a thread about submission videos. Check out the one by Jorge Gurgel, he has also short legs and shows a technique to overcome that problem.

what about general hip training? swimming anygood lol?

if your gonna stay big and want to be good at grappling u should try and develop your top game on the ground a lot

im not saying dont practice from the guard but mostly target your training to being on top because being strong like u said u were most of the time means it is very hard to sweep u but make sure to have good submission defense and that dosent mean if a guy has u in a triangle slamming out of it

techinque is just as important for big guys as it is for small guys

Deadlift if your back can take it... there's nothing it doesn't work and will make you ex-plosive.