Each approach/delivery is your signature and there is no true "wrong" way, just easier ways.  I agree, looks like the arm is pulling you off of posting.

I would suggest that maybe you play with keeping behind the ball.  Learn to rip up/across the back for your revs, as opposed to spinning around the side.   Personally, after push off, my ball swing is very much like a pendulum. I push the ball towards the mark, stay behind the ball on the back swing, and rip through at the bottom as the ball comes off my hand.  Round housing it can lead to inconsistency.  The less moving parts, the better.  Bowler I know, has about 110 300's, and 81 800's motto is Keep It Simple Stupid.  The more you have in your game that can go wrong, the harder it is to find when it does go wrong.  I like to watch Norm Duke, Mike Fegan, and Tommy Jones for their shots.  find some pros and study what they do (via youtube) and try and copy them for the parts that work for you.

It will be a lot easier to hit your mark if your only direction of the arm swing is forward, without the go around.