Might it be an idea to make prox. mines so that they only take 90% of your health instead of killing you? Would make them more true to real mines, which only cripple instead of killing so that the enemy has to take time healing the wounded. I also think no class should have more than one mine. But I know, this'll require extensive testing and so on...
As for AV mines, what about having them be buried upon deployment, like the mines in FH2, with only some part of them sticking up, or some sort of warning marker or whatever?
"One of the bitches actually gave birth while she was attacking, and her puppies joined in on the carnage."
--the awesomeness that is Boatmurdered.