I tried a T50 and found it to be a fairly odd riding bike. The one I tried had these really massive heavy touring wheels on it and I felt like it drove like a tank. Mostly because of that I didn't particularly enjoy riding it while I do like most of the recumbents I've tried.
I don't see why the FWD would cause trouble with a trailer on a flat path. The guy that owned the T50 I tried lived on a very steep hill and had trouble with the FWD traction going uphill (this is in the winter in the Northeast as well) but I don't think it'd be a problem for your use case.
If you're looking at a T50 due to the cost, do check out the 'Bentrider Online forums. One of the guys who posts in the used section restores lots of used 'bents and has as number available fairly cheap.