Jase,
To be hyper-critical, the colour stauration a little too high in the red...hard to see where the H-alpha/H-beta starts/ends.
Tracking focus etc. Spot on
Layering H-Alpha can be very tricky...as you end up with cyan rings around the stars which detract from the real star colours. Backing off the H-Alpha layer is a possible fix.
Otherwise...hey...you are in a different league...this is a very pretty image...nicely done.
Peter