Reverb is always the first thing I reach for but I’m not sure you NEED to do it in the case unless you want the whole thing to be compact and together. A Disting mk4 has delay, reverb, and a few other FX algorithms and a ton of utilities you might want and its only 4hp. The mk4 also has a two track SD recorder which is really handy for an all-in-one system.
Also, for 2hp less you could look at the Bastl Quad Figarro quad VCA. More options in I/O there. I quite like their ABC for mixing duties as well. A QF, ABC, and Skis (or Hendrikson) would make a nice 20hp VCA/utility/external FX bundle. I don’t mind the wooden panels but to each their own. I’m a big fan of their stuff. The Skis would free up the JF for basic envelopes but can also be a VCA itself. ABC would free CM up from mixing duties and can be “stereo”. I’m also using their Dude mixer for my small, portable system. Its pretty basic but works perfect for my needs.