I think it's rather unnessesary that the suit needs to say "blood loss detected" No shit! I got injured? Also, if the HEV suit DID have an expresso machine, he could say "let me make you a drink" to Alyx (Instead of when she said "let me buy you a drink")
Actually you can see the back without cheating. I do all the time. Ever heard of Garry's mod? There's a mod for it called Gmod+ that lets you spawn that suit as a prop, but you can go right through it. And using a combine suit would be fun. You would probably have very little health (as you can get hit many times and even with energy balls, but they die much faster) so you would be doing more of sneaking missions. I want to do sabotage missions in which you only kill about 5% of the enemies you find, and they die by means other than a gun.