Yes, it's about team effort. That doesn't mean they have to be together all the time. In fact, most missions I played, either as a player or a GM, ended up with the team splitting up because of exactly that, to apply their strengths where it's needed. If you prepare a second challenge, a fair and fun one (not something that difficult, something he should statistically win), to test on one of their weakness (or force them to think of something clever to avoid it), then you can gauge the level of difficulty you want in your game more easily. Their strengths stay useful and they'll have original challenges to overcome too. Important to test both. Otherwise, you end up trying to design an ever biggest baddest evil guy for your Street Sam, the ever more secure node for your hacker, and so on, for each of you mission. That is the most difficult AND unimaginative way of designing challenges for missions. You'll force your players to stay (or become) one trick poneys and everything gets old pretty fast for both players and the GM.