For the feeling I want to get from this game:
I want to fear for my life and fight for survival. I want to feel I have a chance of making it happen, that it relies on my skills, even if the success rate is slim. Think Demon Souls.
For the way the game can present the player within the game, solo or within a team, or how the combat can work, I have thought about it for some time and I do not think there can be an easy answer. I think there should ideally be a game design per role... or group of roles. Let me clarify.
Obviously, Solo's make us relate to our favourite action games (usually FPS's, but in my case Dark Souls is more like it - though it did not really handle long-range combat greatly, I think). But the thing is: I personnally don't like FPS's. I would be disappointed if this game ended up as a good revamp of Deus Ex in a cyberpunk world.
Tech's are a little hard to think of. They rarely survive a PnP Cyberpunk game alone, of course, but they are an asset. Of course it is easy to just dismiss them as NPC's that can support the player.
Netrunners open up for a whole new gameplay and I like the idea that the game can just show different settings and environment when you hack in, but the rules have to be different from the real world (otherwise it just gets boring). I have a great memory from a game I played with friends where reality and net were kinda linked (you hack into real life objects, but also there was this dude with existence both in the net and in real life...) AI's have also played a great role in many of the novels I read, so it would be a shame to give up on this aspect of the game if you choose to play Solo.
That's not to talk about Fixers (who could just deal you mission objectives, but then wouldn't it be nice to take part in the political game of influence over your network of friends-that-are-ready-to-sell-you?)
So I get the feeling that you have to build a team, and to assume different roles during the course of the game, to receive the best possible playing experience.
That still doesn't really say how combat can be handled, of course. But it wouldn't make sense to go into hand-to-hand combat without receiving support from a well-gunned-friend, would it?
EDIT: I forgot betrayal. How could we have Corporations without Loyalty - and lack thereof?