In my mind, the problem is that the recent gigs have been so incredibly good, it's hard to pick a favorite version of the repeated tracks.
Here's a couple ideas, though:
BB2 featuring only tracks not included on the first compilation. So, essentially tracks from AHDO, RR, OWB and new improvs, along with some of the rarities they've pulled back out (Spikee, Air Towel, Spoonman)
How about a compilation of just Darren Price's improv/interlude tracks?
Since the concerts have very different feels from night to night (i've been listening to the Belgium, Dutch and German shows), maybe a disc of softer stuff and a disc of harder tracks?