So here's what I ended up with...
...decided to leave the DS-5 outboard, and instead of the MXR M134 Stereo Chorus, I'll keep using the M83 Bass Chorus Deluxe and M87 Compressor in the effects loop of the Mesa Subway+ DI. Both of which I've been using all along. The larger, more complicated MXR Stereo Chorus unit will stay in the practice room. Note that the Mesa has a dedicated tuner output, with a mute switch... the Polytune tuner pedal is patched to that. I've never used one like this before, so it's a little strange... I'd been using the Polytune in the signal path between the bass and amp as a mute, but this is kinda' nice too.
This pedalboard may well become my bass rig... that Mesa DI is a mighty fine tool. As far as DI's go, it's on-par with a lot of studio-grade gear out there. (take a look at the output options) I think the key to how well it works for me is implementation. I think the guys would be willing to keep a good monitor wedge in the Band Wagon for me. Maybe there are other ways of hearing myself, and it's time to start exploring them... but my days of making trips humping speaker cabinets around are about vetch in vetch-natchy.
The second set of pedals are some that are mostly kept toggled <off>. They're just some fun effects for fretless or my Starfire bass, and will probably just get me into trouble! Anyway, these can be powered from the extra jack on the power supply to pedalboard 1, and can quickly patched right in, or... not.