TC Electronic Polytune Mini Tuner- I own the original. Tuners are kind of boring but being out of tune is amateur hour. Put a tuner on your board.
Xotic SP Compressor- This is one of the best compressors I've ever played through. Make your cleans fatter and give your drive more sustain.
MXR Phase 95. As a lover of all things Phaser and Vibe related this thing is fantastic. I like putting he phase in front of drive pedals to get a bit more of a vibe type sound out of them.
Mooer Green Mile- It's a TS9 but with true bypass and the right chip. Great for stacking with the SL Drive or doing the SRV thing with a clean amp.
Xotic SL Drive- Great overdrive sounds, great Marshall-y tones. The SL Drive in Superbass mode is something people don't use enough. It sounds freaking amazing, stack it with the Green Mile or the Little Fuzzy Drive.
Mooer Trelicopter- I've recently started playing around with Tremolo again after years of ignoring it., and this thing has great reviews. The other option might be a chorus pedal. I like these after the drive pedals for more subtle effects.
TC Electronic Flashback Mini- Having a programmable delay pedal in such a small pedal format is cool. Just store your settings in your phone and "beam" them between songs.
I'd probably put it all on a PedalTrain Nano+ which should be just about right for a Mini pedal board.
Then I'd power it with a 1Spot which comes in the familiar daisy chain or their new isolated power brick.
So that's about it. Why not a mini wah? I don't know, I'm not sold on the mini wah yet. I like the full size pedal for that.