If you want some advice on keeping the drawing consistent I would.

Split the page down the center with the rulers. Draw the left half of the drawing

Then copy the right/left side and use the reflect tool in Object>Transform>reflect to flip the drawing over and then align it up.

That way it keeps your illustration symmetrical. If you are using Photoshop then the process is pretty much the same.

EDIT: It seems like you already use this idea but its not being used fully. Try not to move individual parts of it once the 2 halves are combined. Try and perfect one side then copy it over.

It looks even happier than the last time tbh lol