The first person who hacks out all the fucking smoke is going to have a huge advantage. Almost every single explosion has a lingering smoke and dirt effect for three or more seconds. In cases where seismics are being thrown or tanks are fighting this can be a virtually perpetual smokescreen. Client modifications are inevitable and I will be the first to download them when someone releases them.
I can assure you that being able to see through the shit that a wall of seismics kicks up is more than a .3 second advantage.
The visual shake lingers, but the dust should be more instantaneous. Or it should be very low to the ground, no more than knee height, so that you can use it to annoy prone players.
You've got something going with Canyon's mist that works pretty well. Maybe it wouldn't work with seismics...
How about revamping the particles so that they are constructive to gameplay by making them easy to see through? Seriously though, the mortar is like smoke nade that doesn't linger for TOO long and deals damage. :\
Why is it a bad thing if certain weapons can be used as smoke screens? Think of it as a new function.
Because it's not fun to be blind. Smoke nades were never that well received, and are tolerated only when nobody uses them.