You'll get the best advice in the Tailors Thread.
For me the jacket is short overall. The rise of the pants or the length of the vest is off leaving that gap at the waist. The pockets typically bow like that if the seat is too tight, but since it is more flared on your right side, there may be other issues at play. Belts don't work with 3-piece suits, IMHO. There's a lot of other stuff to clean up, but I won't pretend to know how.....best left to the tailors.