One other point is that if you're going to want all of those sound sources to track evenly on a single CV, you are definitely looking at adding a buffered mult in order to avoid CV voltage droop from trying to connect too many exponential converters to the same CV out. Going smaller means you've got room for one...even if it's just 2-3 hp, in a cab that small, space can get pretty dear pretty fast. As for passive mults...nah. If you're going smaller, like this, lay in a supply of in-line mult widgets instead. Jam as much function as you can get into the panel space; by using widgets, you get more functional space potential.