On toe brakes: All the CAP (or "tango") cubs apparently used toe brakes. My first experience was with 190T & 191T in Atlantic city in 1962. I didn't know any better; thought they were OK. Latest experience is with 195T, and I can truly say: beware! When we picked it up, the brakes were adjusted for a long-legged pilot, and no amount of care would avoid brake application when pressing rudder. We shortened the rudder cables enough to "get her home", but then found out that the brake pedal would strike the firewall at full rudder, which made for lousy ground handling. Adjustment of these things is critical. CRITICAL!
The mechanism is, of course, hooked to the rudder pedals, and is a drag on the normally light rudder pressures in a Cub. It makes slips a bit less of a joy, and seems to get in the way when dancing in a shifting crosswind. Coordinated turns are reminiscent of the PA 22 series; it feels like there is a giant sponge tied to the rudder pedal.
And you should see all the junk that is attached under the pilots seat. In a word, complicated. And definitely not attractive. So, I agree with many others - heel brakes belong in the cub. If you want minimum pedal travel, convert to disc brakes. My favorites are the experimental 8:00x4 units made by Grove Aircraft, but if you can stand the 6:00x6, the Clevelands are almost as good, and legal on a Cub.
Don't put toe brakes on an otherwise good Cub. I go "back and forth" every day between the J-3 and the Decathlon, and never really notice!