IG-86 is terrible. So terrible, in fact, I refuse to promote him. GA benefits aside (but not ignored), there's an argument to be made that you should simply collect his shards, without promoting him, until the game no longer exists. Because he's terrible. As such, I am currently at 5 stars on him (before I knew what I was doing), but now at over 600/85.
Convince me I'm wrong.