I like the A&A Supplement but I don't love it. I like the basic system and hate to add on more and more rules that you don't really need. My example Xenomorph was possible without any special rulings. Just saying, and I'm just one opinion...
The point you bring is painful only because it IS what stopped from releasing the star ships. The "is this really necessary" rule conundrum had me stymied.
You are correct, it is easy to stat up as you did with the xenomorph, but I think NPA's (Non-Player Aliens) should be different from players. Thus they have only 2 attributes Physical and Mental, not all 5. Perhaps it would be better if choosing the 2 most relevant attributes for that NPA from the 5 already established? Or maybe you want all 5 for everything?
Secondly descriptive information: Type, Size, Movement, Armor, Damage, Hit points and Special. to me those all seem necessary but I am open to arguments that one or more are not important and should be cut.
Maybe it is the way it is presented that makes it seem more complex? I thought they were simpler than characters as they have only 2 real catch all attributes instead of 5 like a character.
If you have downloaded A&A (and really why wouldn't you-it's free!) go take a look @Gonster's xeno and compare to the A&A version and let me know which you like more....and why! My goal is a good playable game, not ego, so if I got it wrong let me known!
I hope in all of this you can see (wandering star edition vs original or Gonster's NPA version versus the book's version) I am listening to your comments to help make a good game.