I don't know if others have had the same experience, but I have seen both easy upgrades and low prices on AS trancons out of BOS, which might be another option for you (but I don't fly this route often).
Let me echo the welcome and also say that there are many ways in which I prefer AS and its mileage plan, including MVP status after 20K AS miles. Low or no status flights on the bigger airlines can be very unpleasant compared to AS, and as others have mentioned, you're going to have several of these on your way to the first tier of status. I also think there are a couple of handicapped seats near bulkheads which might be available to you on the basis of medical necessity.