NIght vision is gonna be better at identifying exactly what is in the field. Thermal will show you anything that gives off heat and is fairly easy to identify if you know what you are doing. Most night vision works best with a good IR illuminator. Thermal is generally more expensive than NV. If you plan on shooting beaver go with night vision as thermal wont identify critters swimming in the water as the water makes them about the same temp and it wont pick them up unless its a high end thermal.
Suppressors. Unless you are shooting subsonic 22lr you wont ever get hollywood quiet. Bolt actions or single shots are the best to suppress with subsonic rounds. You can get them pretty darn quiet, but very very few bullets expand at subsonic velocity. The vast majority of bullets, even ballistic tips, are as good as fmj at subsonic speeds. Lehigh defense makes a wide range of subsonic bullets that will expand or fragment. Also anything past about 150 yards and you can forget it, the bullets just drop too fast. Semi auto rifles are still pretty loud with subsonic rounds. However there is a flip side. Shooting supersonic with a suppressor is my favorite. It takes most of the boom out of the shot and just leaves you with the supersonic crack of the bullet. When shooting at animals with a suppressed supersonic round they have NO idea where the shot came from and usually just stand there not knowing what to do. I have stood downrange of someone firing super and sub loads. I was about halfway between the shooter and target. With subs you will hear a pop, pop. The rifle firing and the bullet striking the target and you can pinpoint both sounds easily. When a supersonic round is fired by you, you will instinctively look directly to where the bullet passed by you, and you wont hear the rifle or the bullet striking the target. Very confusing for anything getting shot at. I am running a yankee hill 30 cal can with qd mounts. It is rated for 17hmr to 300RUM. I have the suppressor mounts on all my rifles so i can easily slip it on whatever rifle i am using. The suppressor mounts get expensive quick at about $80 each, that goes for about all the brands. If i was to do it again i might would get a direct thread on 30 cal model and just buy an adaptor for 1/2-28 threads, which would fit all my ar's and any 22-17hmr.