I probably use smoke grenades more than most players who match, but they aren't very effective because you can't exactly control where they end up. It is especially hard to use on maps which have many slopes/variatons in them, which is typically all matching maps.
I suggest that there is a smoke grenade option, where it will stick as soon as it hits an object. This way you can control where the smoke will emit from. Beefing the time it smokes would also be beneficial.