Commercial blinds by Beavertail & Mud buddy work good. If you hunt with a dog you'll need to add a dog door in beavertail. If building yourself build something along lines of Mud Buddy style as its easiest to construct. The important thing on any of them is to have your brushing close in over shoot slot which is easy enough to do with either artificial or natural brushing. A product called blind grass works great as your exterior grassing. Synthetic so it doesn,t soak up water and lasts a long,long time.I have an 18x54 boat , looking at building a blind for it .
I hunted out of a boat years ago with a Bert Flemming blind and really like it. But can’t find any pictures of one
Hunting bigger rivers and timber