I was on the North Fork this past weekend. We didn't get very far because of new snow. I wasn't on either of these routes but I can give you an educated guess on conditions.
The East Buttress gets a lot of sun exposure. If you wanted a route that has minimal snow this would be a good choice. especially compared to the East Face. Even so it'll still have some snow on it. Temperatures are forecast to get warmer so it's possible this route will be relatively snow free soon.
The Fishhook Arête is normally a pretty cold climb. Even though it's south facing it is usually windy and cold up there in the mornings until the sun warms things up. During the fall it stays pretty chilly. It also keeps snow longer. The top half of the route (4 pitches or so up depending on where you set belays) gets more sun than the bottom half.
The hardest part will be the approach at the moment. There's 1' - 3' of new snow in the high country right now. It makes backcountry travel pretty slow going, especially when you're off of a trail. The approaches to these climbs will be slow and cumbersome unless some of this snow melts. It will in the sun but it'll be very slow to melt in the shade, which is normal during the fall. Here's a picture I took from Lower Boyscout Lake on October 7:
