What about a house rule in which they could "bombard" enemy units in an adjacent land territory, with the enemy only able to return fire with their own artillery? I think that would make artillery a lot more useful, as in my experience nobody ever buys artillery... Ever.
Seems like it would be pretty balanced... Thoughts?
I think your crazy.
Artillery are extremely useful units IMO
Think of it this way, 1 tank cost 6 IPC and attacks on a roll of 3 or less.
An artillery/Infantry combo cost 7 IPC (only one more than a tank) attacks on 2 rolls of 2 or less (roughly equal to 1 roll of 4) and you have 2 units instead of 1. So more power and more units at only slightly higher cost = more efficient.
In comparison a tank/infantry combo has the same attacking power of a artillery/infantry combo and the same number of units, but cost 2 more IPCs
Historically artillery in WWII could not even remotely come close to the range your talking about.
And no it would not be balanced.
The game is pretty great as is, in my opinion.