Yes, and I try to avoid that artificial feeling wherever I can. It's difficult however, since you have to spin so many threads over the duration of a campaign, just in case the players finally decide to tap into one at a later point nonetheless. That's why I usually ask my players what they would like to do during downtime, if they want to schedule a solo between regular sessions and we usually have one of us (mostly them) write a summary of the last session before the next.
We also use a character pool system, so people can switch characters (and thus roles) between runs, playing what they like within one campaign. It works really well and three out of five have experimented with a second character, one aims to do so in the future and only one player showing no interest in a second character since he is highly invested in his samurai. Which is fine by me as he somewhat took the role of my leader, when I stepped in as game master.
With all the action, mutliple story threads and various meta-plots on diffrent levels ('corps, racism, national level, magic, organised crime) I also try to stick it not too often to my players. I want everyone to leave the table with a feeling of having spent his spare time on something worthwhile and that means most of the time the runners succeed. They play good, plan ahead and although there have been stupid decisions, really bad roles and simply ugly days, they have made contacts, friends and money so far. We all know, that might change at some point, it's a gritty world out there, but I don't force it. In my opinion, trust is easier gambled away than earned, and that counts for teachers, leaders and game masters all the same.
To ensure that everyone can play, what he likes, while not inhibitting the major plot lines of the campaign, we agreed on a couple of simple rules. The basic group of runners all know each other from before their lives in the shadows. They worked together for Fuchi and defected when the shit hit the fan in mid 2060. As long as they remain off the radar, they might be able to pull it off, but if they arouse to much attention, Shiawase and Novatech, which bought most Fuchi-assets, will notice that they're still alive and try to "seize their assets". So the main goal is to survive. In each run at least one member of this "Original Six" (including my character) needs to be participating. Everyone else can play characters from his pool. Characters that are not played receive exactly the same karma and payment during their downtime as the rest, so there is no immediate drawback of a character resting for while. However loot, contacts and bonus payments can only be earned in-game. If you miss a run, you don't get any of these. If you miss a session however and your character participated on the run, you are entitled to all the benefits. I don't punish players for missing a session, as I presume that everyone wants to play and my players often work nightshifts or weekends. So missing a session is punishment enough.
Everyone can ask for solo sessions or other extra sessions with less than the full group present to play more narrowls focussed stories around one or a few characters. These are not runs per se, so there is no set payment or karma. In fact these are usually session, in which players spend money on organizing gear, playing initiations, make contacts or anything like that. So my players have to come up with more ideas from themselves here. Technically, they can earn money, if some NPCs offers thems, but there won't be karma at all, since I want all of my players to have equally skilled characters. I made the experience that people, who play less often often get the feeling of being left behind, if their characters have less karma. As I said, I don't like someone feeling punished for working hard, having wife and children or choose between his long distance relationship and fun with friends. So, while I cannot and will not stop people having fun on solo missions - and handing them goodies - I won't offer karma.
I have received extremely positive feedback (did an anonymous online evaluation a while back to be sure) and I think everyone genuinely likes the team performance. So that's that. If anyone likes to experiment with our team rules, feel free and I'd more than happy to receive feedback from you, too.