Opening theory is the least of my worries and next to non existent these days to me.
I prefer to spend my limited time on basic tactics training, middle game plans, ideas, strategies and end games.
And having fun.
e4 openings are more fun because they are more open, tactical positions. You don't need to learn so many lines of opening theory when you have the tactical instincts to play e4 openings.
Yeah, I could see Bg5 being better than Bf4, will concede that I hadn't thought of Bg5.