Tesla cannon seems underpowered at first, but it is the only weapon that can be fired while your shield is up. I don't know if this is by design but I think that unique functionality makes it balanced even though it is weaker than other weapons.

As for the shotgun (flak cannon), it does seem a bit OP. It's certainly the weapon I use the most, followed by the grenade launcher. Switching between flak and rocket is a particularly good combo.

Depends on the proximity. They are OP on the base map IMO cause mechs get close on that map. You can dodge them if there's time to react but oftentimes there isn't if you're right next to each other. I tend to save my mines for when I'm outnumbered or get hit by an EMP so I'm not a sitting duck cause that's a guaranteed frag.

IDEA: They shouldn't detonate instantly but be on a fixed 4 second timer instead.

I'm bumping this since it hasn't been addressed.

You can deploy mines after destruction to frag from the grave and it's annoying since you get near the mech after you've fragged it. It shouldn't be a threat at that point.