General DiscussionInvoker pre lvl 16

I have no idea how to play standard QE invoker pre lvl 16, when invoke has a huge cd, I usually have forge spirit and alacrity invoked, so I can get the highest farming efficiency. But usually I'm not ready to fight if I maximize farming like that, after eul's I'll keep ss and forge spirit invoked if I see a potential kill, I'll quickly invoke meteor to replace forge spirit wait for invoker off cd and do the eul's ss-meteor-blast combo, after lvl 16 espically when I have agh's and boT, everything is much easier, I can maximize farming and be ready to fight or split push efficently. Am I doing I right? sometime I feel I don't have enough game impact mid game playing invoker.