Ok as the current war clearly shows, war is only fun for one side and the odds will always be as heavily stacked as possible as cities are put at risk. However fighting set battles on a random tile seems really dull to me.
On the other hand if I only stood to loose a few buildings rather than an entire city, I may be willing to go up against a slightly larger opponent, and consider those few buildings fair exchange for the enjoyment of a risky, yet less destructive war.
Players would still try to stack the odds but I doubt it would be to the same extent as we have recently seen.
Please note that this is a poll about allowing war into the game not about the current war, please restrict comments to flaws in the poll, or suggestions you think are better than mine.
Also the T3 siege unit would not replace current T2, rather it targets say, wall, barracks, mage tower and consulate. As a means to achieve satisfying wars with players you don't wish to drastically harm.
Oh and just to make clear these would certainly be player run tournaments.