What rear suspension for bracket racing.

I voted for ladder bars before i read your post.
For 500hp or less, i would likely just start with ss springs, and some good shocks, double adjustable if they fit the budget. A definite step up, especially if moving springs and mini-tubbing would be caltracs and mono leafs. Probably could still use the good d/a shocks from the ss spring setup.
Back-halfed with the frame moved, ladders are a no brainer.
In my humble opinion, a pinion snubber is five pounds of utterly useless weight, much better in a round file than my car. The only way it might work was if it is against the floor. The rearend of the car is supposed to lift, and push the rearend down. If that is what happens, what does the snubber push against, the car floor is now two to four inches away? (And im sure the ride is real comfy with that snubber against the floor, driving around on the street.)