The 2235 works very well in vented cabinets of 2.5ft3 to 10.0ft3, tuned between 20Hz and 30Hz. For a wide range operation, I'd prefer them in 2.5ft3 to 4.0ft3 tuned to 30Hz. For deeper operation, put them in larger 4.0ft3 to 8.0ft3 cabinets and tune them for 25Hz. And for subs, you can max out the box size at 10 or even 12 cubic feet for an EBS alignment tuned to 20Hz.

About bracing, you know that you can't really brace something like this too much. There are some situations where stiffening something or holding it more firmly can cause other problems, but this isn't one of them. As long as your braces don't make it difficult to service, I say put 'em in.