Simplifying a little.
Played a gig at Sundance with just a Venue and an A/B switch (I didn't want to wag around a ton of gear in the snow) and thought my mandolin and banjo sounded good, so I got a PZ Pre to replace the pedals for banjo and mandolin and it sounds killer.
Alas, the EQ and gain settings for the guitar are different enough that it still needs its own box.
Before:
After: