Another change beside his E perhaps make his Q more effective

For Q I suggest addition to the passive, if he kill unit will add 1 to his SS, but if he kills unit with SS he add 3 more (4 in total) to his Q, but I don't know if this number could be so OP the idea is just he gain small extra damage even if he doesn't use his Q to kill unit.

or it could be same as 3 but gain like 10-15 if he killed enemy champ, so killing champ is more rewarding..

For the number perhaps riot will know better if they apply this, I just can suggest the idea.