FYI most of my recent experience is of moderately dense games: something like 2v2 on a 12x12 map.
My problem with Lance is that in moderately good hands it causes a whole lot of problems to counter whilst itself requiring little effort to manage. It seems like it's not unbalanced, otherwise it would proliferate in all game types, it's just quite unfun to deal with in battles where there isn't an obvious hole where the Lance isn't. Typically as soon a Lance appears I have to do one or more of the following:
- Concede territory that I can't defend without huge losses.
- Rush in and trade really badly with the inevitable riots / point defences. Lance retreating plus ability to massacre groups means this doesn't go well.
- Wait for several minutes to get some planes, probably a Licho to have much chance of delivering a shot. This is expensive and usually comes too late to turn the tide.
AFAICT there's little point in trying to get your own arty because Lance will just take that apart bit by bit, plus several facs don't have one with enough range to cause problems. In theory there are other plans like those involving Cloaky, but I have even less success trying to coordinate Imps for example.
Overall if a Lance appears in a relatively balanced game and I don't have enough army to push through and kill it right away, I'm pretty much doomed to lose.
My feeling is, if Lance has to remain as awesome as it is (and it is fun to use), then it should be made more difficult to use as well. Something like making it very difficult to retreat after firing, or more prone to causing damage to ally units, for example, but I'm sure there are other options.