Pentagon please.

Well my vote would be with continued development of Rapture Pro and Z3TA+2, since those are the ones I tend to use the most, and I already own them. Also they're all the ones Bandlab is most likely to be able to sell as add on products, since they're the most modern and relatively established in the market. But I'm not against revamped versions of some of the older properties.

I'm in no hurry to see a new version of Z3ta+ as I think it's pretty complete.
 
On the other hand, Pentagon I could use a bit of work.
 
Similarly, while I enjoy Rapture Pro as a preset player, they need to rework the interface.  If I make any soundsets for that one, it's far easier to do most of the work in Rapture classic.