Oh you mean Hooni? He barely plays lol. Pretty sure I'm the reason why flashbangs no longer flash the user (or at least no longer flashes your team) as I was one of the only few that actually made an attempt to use them.
There's not much that can be done to keep players (hooni) from spamming them in game. Most players who even use them try to use them in a more tacticful manner (puta/Guide)
If any of the nades need a revision it'd be smoke nades due to the fact that the only tweak that's been made to them was that they allowed them to damage other players. I'd like to see them work on the smoke nade radius as the radius tends to be very confusing at times. It also doesn't help the fact that the smoke isn't stationary like molotovs are so the damage "cloud" spreads pretty far honestly. And to add in the fact that all nades do NOT FOLLOW anti leading rules, it makes for the smoke nades to be even more difficult to use/make useful. I've had many times where i get 10+ ticks from smoke nades yet my damage counter remains at zero. Pretty frustrating.
As for molotovs i think they could do something with the radius to damage ratio where the radius could decrease the longer it's activated or somwthing along those lines.