The old rule of thumb really does apply:
You can have two of the following three:
- Small
- Loud (high SPL)
- Low (deep low end)
The Acme's give you the small and low, but are very inefficient. An Acme 210 will give you more low end than most 215 cabs, but will not be as loud as many 112's.
I've taken a very different approach.... Loud, Low and Light... I can have all three of these in a relatively large neo loaded/ultra light plywood cab like the Epifani 410ULor 310UL, etc. I've found that, in my situation, weight is more key than size. In other words, as long as I can easily lift the cab by myself (up onto high stages, up flights of stairs, etc.), then the size is quite secondary. My Epifani 410UL is 56 pounds... amazing, and the SPL and low end extension is just stunning IMO. It's a large box, but that's what gives you the projection and low end extension.
There are quite a few nice large, light boxes that might fit the bill. I find anything under 60 pounds, regardless of size, is a total breeze to schlep around.
Just another approach to think about.
However, if you really want 'small and low'... two Acme B210's with about 1000 watts running into them will definitely get you where you want to go IMO.