Canister filters are generally pretty quiet. Eheim classic canisters are popular for good reason, with a reputation for being quiet and reliable. For your size tank I wouldn't go smaller than an Eheim 2217, depending on what type of fish you plan to keep, bigger is better. Good luck with the new tank!
I have 4 canister filters (3 different brands) running in our kitchen/dining room area and I can't hear any of them.. canister filters in general are very quiet. What I hear constantly (and drives me batty) is the drinkwell fountain for the cat.. but there's no other convenient place to move it and be able to refill it, so I deal with it being annoying
You can also start your tank with one filter and add a second later on as your bio load increases.
Rena Filstar XP 3, would that work for 90 as well?
Should I consider 2 filters?
How would I put my UV inline or would I need it own pump?
The Rena (now API) is a fine filter. They also make the XP4 with another chamber for media. I have one, it is very quiet. So is my Cascade. Cutting in your UV sterilizer should be no more difficult than cutting your canister return line and plugging the UV in with a couple of barbed fittings. Or if you need a little more slack in the tubing buy a couple feet at the local hardware store. One nice thing about the API XP's is that they come with silicone tubing which doesn't seem to get stiff over time. I also like the flexibility of the outflow and return hardware they supply. I'm not real fond of the blue color of the siphon tubes, but that is really minor.