If you are going to be mowing the 11 acres or a significant part of it with a rotary mower, the 1/4" valve on the B2x20 and other B's except for the xx30's is a disadvantage. I use chains to keep mine at the height I want it. You will otherwise be bumping up the front of the mower every 10 minutes or so. For the other things I do, box blade, rear blade, spraying, the 1/4" valve works fine. If you are going to be using a RFM, the 1/4" is fine.
The Lxx00 series tractors will give you the position control. There are numerous threads documenting the system is jerky when raising the implement so the suggestion is have the dealer put a heavy implement on it and raise it and lower it especially in small increments to see if that bothers you. As you mentioned, they don't have the mid pto capability, so you have to decide if that is an issue for you. When I sat on one, I did not like the placement of the controls as well as mine, but that may be more of a familiarity issue.
The Bxx30's are really nice with some good features. Strong hydraulics, position control, telescopic stabilizers and links on the 3 pt hitch, etc. They are more expensive. The only negative besides price to me would be if you add a MMM on them, it is a ground contact so the wheels ride on the ground and support the mower when mowing instead of the suspended mower deck used on the B2x20 series tractors. Some put chains on their decks to convert them to suspended though.
It seems there is no perfect solution. If money wasn't a big concern, I would probably look hard at the
B3030 and live with the mower deck or just get an RFM. On the 3 acres I live on, which is basicly a big yard, the
B2920 is perfect for maintaining it, the 400 ft drive and other projects. On the other 11 acres we own which is a mix of fields, rough fields, brush and woods, something bigger, heavier, and stronger would be a better option, but for now I trailer it to there so don't want something too big to comfortably trailer.