Shimano Xt/slx-personal experinece-well priced, well made, reasonable weight, utilitarian looking, best all rounder probably.
Avids-From personal experience again,wouldn’t bother with the juicy’s. Good performace, but never got a good feel. Bleedings a bit of a faff comapred to shimano. Spares are hard to come by and the pistons have a habit of seizing
Hope M4- some love hope, some dont. Good spares availbilty and custoemr service. Look great, and endless list of custimisation available.
Magura-Seem to get rave reviews, 5 year leak proof warranty, german engineering.
Would also be tempted by Formula The On because they look so nice!