I came up with this the idea of a landmine secondary weapon yesterday, it could have a set time to plant (maybe 5 seconds), a set time to "reload" (maybe 15 - 20 seconds), and would disappear after rounds to make sure people can't just plant too many. The damage output could be about as much as a melee, or higher, to compensate for the long time it takes to plant/reload.
I don't know what your planning for the future, but this idea came up, and I thought, since sanctuary is still in beta, that is has a chance to be added. It could also be a useful tool since your planning on removing kiting.
Note: I've already obtained other people's opinions on this yesterday, so that's why I'm making an effort to post this.