Need something more than "PC specs optimal" Tell us your specs. Have you updated drivers recently? Windows? Are you running mac? New GPU? Any new hardware? software? Have you verified the game cache? Have you tried uninstalling and reinstalling? Have you tried manually wiping out the game contents folders as opposed to using the steam uninstall function? Have you tried different games? Have you opened your computer case recently? Any BSODs? Are these bug splats you're talking about? Dump files?
Would you require 2 models for the full effect? So 2 models would put away their weapons and grab a bottle? What about the throw speed boost at vet 2? Would that stay?
Sounds like a large change in my head with a lot of repercussions that would probably require extensive testing.
I think the KV-8 is very strong, maybe too strong for the timing it comes out. If you go p4 or fall behind early you're essentially at the tanks mercy due to its ability to 2v1 AT guns. I don't think the idea of buffing the brummbar to obscene levels again because another unit is strong is a good idea though. I also think the KV-8 is simply overshadowed currently by heavy tanks since they're essentially able to 2v1 AT guns now as well.
Now I don't know about free, but I think a shift in the pyrotechnics upgrade price and a small fee for smoke throwing as well as the shared CD may be good IMO.