Several issues arise, what boards do you have? Do you like them? If so and you don't want the next gen boards(thin cardboard), then run to MMP and get everything in stock, and go to e-bay and finish off the list.
Next FKaC is good, but WoA is better, go to e-bay and get it.
CoB is necessary next, go to e-bay and get it.
GH, get from MMP, they are starting to run out!
Italians next...HL.
French CdG next
Last Hurrah next
Hopefully AoO is out and you preordered it.
DB..your last e-bay adventure.
Grab Para cheap at some point, just for the board, funky armor counters and scenarios.