Based on many discussions here on genoa size, I don't think you can go wrong with a 135. Some of us have gone smaller, however.
The idea is that with roller furling we basically have one headsail, and furl it to different degrees. Big headsails are of light material to work well as light-air sails. However, if you enjoy sailing in 25 knots occasionally with the genoa furled 80 percent, that's tough on lightweight material.
So it's a compromise, as usual. Dacron is a fine sail material, and the heavier it is the longer it lasts. If you're working with a local sailmaker or rep, I would value their opinion more than my generic remarks.
Any new genoa is great. Be sure to get a foam luff. Oh, and welcome to the Ericson Yachts forum.