Not really no. Back on topic. We have talked about turrets but what about mines. Harder to see and go boom! We know the operatives can see mines but only other engineers can defuse them. When they defuse them should they get the mine? Should you able to upgrade to to a OHK? How to improve? Bigger blast damage, DoT? GO!
I will use things from previous SD games to maybe get a "feel" or idea of how things could work in Brink:
In ET, mines were undetectable. You could not spot them like in BC2, since they were planted underground, and although Operatives could see them, they needed to use binoculars to be able to spot them - they didn't just automatically spot them. Also, if you stood on a mine, you would hear it trigger, and if you didn't move off of it, an Engineer could disarm it under your feet.
Then you have QW, where mines could be placed on walls and act as tripmines. Also, you didn't have to actually arm them - they would automatically arm after a few seconds.
Mines pretty much [censored] [censored] up. If you triggered one, you were dead, even if someone near you triggered it, it could still kill you.
I think that mines should be brutal and be able to OHK - act as one of those things players need to be aware of and be careful of. The types of upgrades for mines I would have would be things like increase the amount you have, make them completely undetectable (or much harder to spot), decrease arming/disarming time, or maybe an ability to have remotely detonated mines, rather than proximity.