I would definitely recommend taking your horn to a tech and checking out your mouthpiece reed set up first. I play all Buescher horns currently and I think they are very easy to play. A while ago there was a pull on the most free blowing horn and the Big B came in pretty high on the list.
Which model Buescher do you have? What is your mouthpiece and reed set up?
Keilwerth are great, and possibly easier to blow, but cost something like $4000 new (or you can buy my used one for $2,500

). I'd imagine, if your Buescher is an early aristocrat (pre 350,XXX) it could be an excellent horn for a couple hundred bucks of repairs.