I like the idea of changing the drivers to the 7″. They will be more bass heavy due to the fact the 7″ basically have a baffle step built in already. But for music, that will be pretty enjoyable. If it were me, I might consider switching the weeter to the Peerless ring radiator. BUt that is really just a personal choice, as there is nothing wrong witht he Dayton. I just am very fond of the Peerless at that price point. I didn’t mock up the box and I didn’t see it mentioned but are you going sealed or ported? It seems the box will be rather big, which would concern me as it might lower the power handling. Of course, it might be more than enough. I haven’t modeled it. However that is definitely a graph I would check in winISD when you are modeling it.