the reload reduction from 5-ish to 3.25 s may sound pretty over the top at first glance, but if you factor in additional delays (wind up/wind down, aim time, etc) it comes down to about a 30% increased ROF. that's pretty substantial for sure but i don't think it is op, simply because we're only talking about the barrage here, not autofire. i'd expect the 120mm to be quite a bit better than the pack howie at close range and about equal at max range with these changes, but we'll see if that turns out to be too powerful. at the very least it's likely that a lot more people will try this thing out again for once after being left in the dust for quite a while, so it should become pretty obvious rather quickly if this buff overshot the mark.
I don't think the RoF will be over the top, it should be about the same as the 82mm now with more AOE and range but less accuracy. It will be better than 82mm that way, its doctrinal after all. But you will need 82mm for sight nevertheless, that will reduce the number of 120mm you will purchase by one at least.
Imo the question is how good is the Vet1 barrage. This ability has the potential to overperform of course. Is it a exact copy of the USF mortar HT Vet1 barrage? Does somebody know?