In this block, I did what I always wanted to do ever since I bought these two prints: I used them in one block, and only them. I thought it would happen earlier but it seems I had no opportunity so far.
With this block, I think it is essential to use only two different prints. I saw examples where the centre square or even the centre strip had different prints/colours, thus totally destroying the motif. You were never able to see any bat in them. Keeping it simple is often a good design recipe, anyway.