I've always read that you want an even tiller to shoot 3 under but, I only have one bow tillered even, the rest are tillered about 1/8 strong and I don't notice a difference between any of them. Brace height hasn't had to change for me but, your nock point will probably move. 3 under typically requires a a little higher nock point. One of the bows I'm shooting now likes 7/16" above square, the other a little over 1/2".
I agree...never noticed any difference in noise in different tillers. I had a Hoyt Buffalo and adjusted the tiller to dead even just cause I could. It was quite enough so I just left it there. Killed a few skwirlz and a small buck with that bow. Darn good shooter.
The bow will determine to arrow nock height. I have a mark on my square where I start. Side note, that mark is on a square that I hate but that mark has been there for years and I have no idea what the measurement is. I have a bow that likes it almost dead center even and I have had others like it a little higher. A second nock under the arrow is the key. I use brass for the top and once that is figured out I tie another underneath.