one thing i can tell you about draft, my buddy has a 20 ft angler "bay boat", he needs at least 14 inches to float in, and depending on my load, i can float in 10 inches easily, and thats with a heavy v-6 on the transom... when i had the lighter v-4, 8 inches of water was all i needed...
most "bay boats" now a days need at least 12 inches or more to float in. and most deep-v boats require more water...