Build pacifists. Nothing but pacifists. Every week he'll martyr the PCs and every week your doctors and scholars and slicers will return with different names - fragile yet immortal. And after around the ninth time you can ask, "Are we allowed to have fun yet?"
(See this response is why I'm sometimes accused of being passive-aggressive.)
Shouldn't that be pacifist-aggressive in this case?
Sorry - really, sorry. I couldn't help it.
Seriously, it sounds like you've had a word with him by yourself (which is cool - you're friends, so you don't want to try and shame the guy), but if he's unwilling to change based on your friendly chat, it's time to talk as a group. Not to him - with him. And not about him - about the game. (Sounds like you know that. )
At the start or end of a session ask everyone if they think there's too much combat. Bring up the elements you'd like to see more of (trickery and social engineering, stealth and sneakiness, puzzle-solving and tech savvy - whatever) and ask everyone what they enjoy (use examples from your GM's game where you can). Talk about the tone of the game - does this feel like any of the films? (I don't know the context of the cyborg death squad, but it sounds more Warhammer 40k than Star Wars, to be honest.)
Be prepared to compromise, obviously. It's his game too, so the elements he enjoys need to be present as well. There's a balance to be struck that'll leave everyone happy.
Actually, respectfully I'm going to disagree here. The reason being that whilst some people are able to handle everyone suddenly bringing complaints to them, for many people it makes them feel like they're being turned on by a group, ganged up on, and generally to feel bad / act defensively. A co-ordinated response from the players is good, but perhaps individual approaches saying essentially: "we don't want to have to make combat-optimized characters, we'd like to be broader, but we feel we wont survive in your game if we don't min-max everything".
Note there are other reasons why a GM might be putting all this in the game than them enjoying combat. For example, in my Shadowrun games there was frequently some horrifying opposition. The reason wasn't because I wanted to over-match the players or run a meat-grinder. It was because that was the opposition I felt was realistic for a given scenario. My D&D-background players constantly wondered why I was throwing all this horrendous opposition at them. Whilst on my side of the screen, I kept wondering why on Earth they'd go crashing into a secure corporate facility without preparation. Eventually they realized that, figuratively speaking, the dragon lived on the mountain whether they went to the mountain or not, and that they were actually in control of whether they wanted to face it. (To a degree, at least). Perhaps your GM is like that - simply constrained by what they think is appropriate.