Designing dilemma

I am currently designing a series of-- for lack of a better word-- "Tiles".  There will be at least 4 of them all using the same colors which can be framed, of course, but would also be great to sew into a quilt or wall hanging.  My dilemma is whether to release them one or two at a time or all four together.  Any opinions would be greatly appreciated.  I've thought of releasing them all together in one chart at a higher price but then I've been thinking that stitchers might prefer getting them individually at a smaller price per chart.  What do you think?

The models for the first two are being stitched now and the other two will soon follow.  Then I will decide whether to add the last two or stop at four.

Thanks for stopping by.  Until next time...