I love the panel and how it is looking so far. (ok you asked for an opinion so...here goes) I would lay out the hex's next to the 7th panel that you got for the back and "work it into" the whole top. Of course if it does not look too good, you can scrap the idea before "cutting", etc. etc. Hope to see the whole thing finished.
I had thought of using the panel as a centre piece and arranging the hexagons around it Ellen.....I want to keep the last panel as a whole, but I might use the part panel to make blocks...not sure yet...so we will see what evolves, like all of my projects lol!!