I was really excited when I saw this question on the list, but now I've come to answering it I've changed my mind. I've written and rewritten my response, and come to the conclusion that I don't like the idea of a single 'dream team' for several reasons, but the main two being 1) I've played with far too many fantastic players I'd want to play with again to narrow it down to a single team; and 2) of the fantastic players I'd most like to play with again, I don't think playing with them together would be as satisfying an experience as playing with them in the groups I originally played in. The third point follows from that: I don't want to get stuck seeking to reclaim former glory, but would rather use those memories to build more fantastic experiences. Or maybe I'm just afraid that trying to recreate former great experiences would fall flat from the pressure of expectation. I'd rather move forward - I'd love to play again with so many people I used to play with, but I don't want to create some kind of 'dream team' pedastool to measure future groups against.
The (old) World of Darkness campaign I played in at uni was possibly the time I found myself deepest part of a team and probably is my yardstick, but I don't know what it was about the game/group that worked so well. I think partly it was my first exposure to World of Darkness, and the interpretation of particularly the Werewolf lore struck a chord deep in me. The game worked well because for the important things I think we were all on the same page. We had the same goals, I guess. The pack came first: we were bonded as a team in a way I haven't experienced in many games (I think this is part of why I love playing twins in Exalted). The GM and other players are all immersive players and, where necessary, were emotionally supportive of each other outside the game where it related to things caused by the game. And I phrase it like that, because I could never play with that group again, because eventually I had to cut off contact with the GM because his friendship beyond the game was emotionally damaging to me. So maybe that's another reason I'm struggling with this question: the best players aren't necessarily the best people, and I'm remembering a lot of toxicity.
Fortunately, most of the people I've played with are wonderful people, so in the spirit of the question, I'm going to give you a largely meaningless list of a few people I've gamed with who've left a particularly strong impression.
- Miriam: I haven't seen her since I was 18 (which is reason enough to miss her), but she was a few years older than me and as I got older things she'd said in and out of games would come back to me: she, more than anyone, gave me the keys to becoming an adult.
- Charlie: I set up a roleplay game as an excuse to get Husbit's number (being too shy to just ask for it), and realised I needed players. Charlie was my brother's year at school and did panto with me, and had never roleplayed before. Despite that, in my abortive ShadowRun campaign her character - a tiger shaman who'd had whiskers grafted to her face and was covered in a tiger pelt tattoo - was the most rounded and, for me (despite the silliness - maybe because of the silliness - of some of the others) the most memorable.
- Mel, Gog, Boyd, Sith and Ed: for the WoD game mentioned above. Boyd taught me everything I know about tricksters. Sith also ran the Final Fantasy Noir game where I played my beloved Kella.
- Rowan and Gem: two of my best friends. Rowan runs largescale games (like the Cyberdoggie game last New Year) and played Reisha against Kella (so again, that moment of playing characters with a deep bond). They both LARP and Gem has recently discovered she prefers reffing to playing, and nearly has me convinced to join them some time (not quite, because it's potentially very expensive in time, money and energy).
- Monty and Troll Luke: they developed the Dockyards setting where I had my character Kismet. It might be my favourite setting ever.
- Bells: of everyone I currently play with, Bells is the one I've enjoyed playing with most. This is probably because in both Aberrant and Exalted our characters have a very tight bond, and looking at this list (and several other names that I've considered and disregarded), having a bond like that with other party members strongly enhances my experiences. Rich, who usually GM's, has ideas on building a similar bond between our Deadlands characters, which is exciting.
- Husbit: we met through roleplay, but interestingly haven't yet played together with strongly bonded characters. All the same, I do love playing with him - though maybe more when he's the storyteller.
You see, now I just want to list all my closest gaming friends. That makes this hard too.