I'd highly recommend getting out the islands, although you might be a little short on time, depending on how long the conference goes, but if it's in downtown, the ferry beats driving and is like $10 or less. Peaks is the closest, and has the most restaurant options as well. Long Island is good. Others are less 'available' to the public unless you're staying there.. Come to think of it, that might not be a bad thing to just get a place on the island especially if work is paying for it..Peaks ferry runs something like hourly or more until fairly late, and takes15-20min

If not staying out there, should still be able to fish off the docks or walk to somewhere close (use Google Maps) . Have only fished off Cliff on my own boat, but have seen folks fishing on other islands.. Others may know more about specific spots.

Here's the Casco Bay Ferry schedules and site.. be sure to read about the islands & do some research! https://www.cascobaylines.com/schedules/