Playing at brigade level would remove too much of the particularities of napoleonic warfare, imho. You can't order a full brigade to form in square (and if you do, it shouldn't be a question of "all or none" are able to), you can't keep tactical reserves if you have to charge with all of the brigade, etc. That level would require too many abstractions, at least for the kind of game I like.
Raimon
It is all a question of who you want to pretend to be. If you want to be a brigadier then you want to order battalions into squares. If you want to be Napoleon then you just want to tell Marshal Victor to drive the enemy out of that town and you don't necessarily care what formation the battalions are in. I have played games at all levels and enjoyed most of them, but I confess I do like the battalion-level games quite a bit!
I have never played the Talonsoft games, but I'll happily take your word for it that it can be done. Most of my gaming has been with board games and miniatures which naturally take much longer to play since you are physically moving components and doing all of the measuring and calculating yourself.
Aaron