Most of the games that I have played or run were set in Camarilla cities; so, I don’t have much experience with Non-Camarilla Clans. When I first started playing Vampire the Masquerade, I had a lot of bad experiences with power-gamers playing Assamites. They played the kind of murderous sociopathic characters that I wouldn’t allow in my games now. They tried to diablerize (in Revised) their way through the city’s hierarchy, and if they got the scent of a character with a lower generation than them, that character was going to meet his or her final death very soon. Playing an Assamite for them was an excuseto do whatever they wanted because they could claimed that they were just playing their character, when in reality they were only working for their best interests.
However, I have recently begun using Assamites as antagonists in my Chronicles. They are great villains for a story because players are already frightened of them and their abilities. Quietus, Obfuscate, and Celerity are all powerful Disciplines that when paired to the Assamite’s philosophy and goals makes for a remorseless and nearly unstoppable killer. The first level of Quietus creates a bubble of silence around the Assamite. Using the Discipline loudly announces the existence of a nearby Assamite, but simultaneously that knowledge is terrifying to the players because they can’t see the Assamite thanks to his or her use of Obfuscate. Celerity is usually considered the most powerful physical Discipline because it gives the character extra actions.
By setting the scene in a burnt out tenement building that is crumbling and creaking, the players will be as frightened as their characters when you say “You try to talk but you can't even hear yourself. You hear nothing, nothing at all.” The players panic because they know only an Assamite’s Quietus has that effect. An Assamite, a member of a clan known to hunt and kill other Kindred for their blood, is in the building and the PCs can’t hear him/her, can’t see him/her, can’t do anything but wait. It's a great moment and I really enjoy watching the players squirm as they try to figure out what to do.
Despite my early bad experience with them, the Assamites are my favorite non-Camarilla Clan because they are useful as a tool when I’m the Storyteller. I don’t think that I would ever play one because their attitudes and goals could be disruptive to the group. If I was to say which non-Camarilla clan I would most like to play, I would have to say True Brujah, despite their reputation and the reputation of people who play True Brujah (those who want to be unique, beautiful snowflakes). I have wanted to play a True Brujah since I first read Dirty Secrets of the Black Hand, and I still haven’t played one. Hopefully, I’ll get a chance in the near future.