Dustbowl: On defense, I've scored my most assists (20), most kills (21), and most defenses (4) on this map. On offense I almost always end up playing medic because I bother to stay alive and get ubers when other medics get themselves killed.
Gravelpit: Three captures as a medic. This map is a blast, and was a close second on my choices. Try getting the entire defensive team to go heavy some time...it's hilarious. Then when the other team tries the same stunt, everyone go pyro on offense.
Well: A buddy and I have mastered the quick win on this map...we have a tendency to be at the fourth and fifth points waiting for the third to be captured...if it goes down, our team wins before the other team has time to think about falling back to defend.
Hydro: It's fun with two aggressive teams, but can get campy and stalemate frequently if neither team is willing to risk their point.
Granary: Sucks compared to Well, with a lot more camping because it's a more linear map that's easier to defend the second/fourth points. Granary much more frequently goes into Sudden Death on servers I'm on because one team will just dig in on points they already control and never try for the next. Well, on the other hand, goes back and forth a lot more.
2fort: What amazes me is the number of people who feel they MUST go sniper on this map, just because the battlements are there. I've seen five out of twelve people on the battlements sniping...and when the other team wised up and just stuck to the water, they just hung out on the battlements waiting to shoot something while our defenses were overrun and the intel grabbed. There's nothing wrong with the map itself, it's the volume of noobish behavior it evokes that puts it at the bottom of my list.
I'm new to this game, so I'm not very familiar with the map names yet, but I like maps with windows and big open spaces where I can snipe. I hate indoor battles.
If you like teamwork and accomplishment, there couldn't be a better map than 2fort.
The hard part is finding decent people to work with. I hate it when there are more Snipers than Medics and unfortunately thats the case most of the time.
I like Dustbowl and 2fort, my least favorite is Granary.
2Fort is almost always stalemate, where as well constructed maps like Gravelpit allow a bad team to at least change attack paths and attack other nodes, giving them options should the other team lock down one node hard they can go for the other. But the last node is a single cap and that requires a little more work.
2fort ruled in TFC - really fast paced map, tight quarters, great non-stop fun. The TF2 versions a lot slower and more open. Ultimately its a port from a old fave, so will hold a place, but not designed for the 'modern' game imo.