let's see on mid:We'll always have FOTM chars but I always thought any class except stealtherq got into a grp easy
zerker: 8v8 king
skald: if they have the room for you
thane: only find grps if you know a lot of peeps and/or are high RR(with atleast ST3). ml8 battlemaster a must.
warrior: will easily find grps if he has BG. If you don't run in a FG with a BGer, most arpees are for non primetime.
savage: no clue, usually there aren't more than 10 savages (of 600mids) max online
healer:
-pac healer: if you're good, you'll be begged to join grps from the moment you log in.
-aug/mend: finds a grp easily too.
shaman: most FGs run with one shaman they know, other than that it's not too hard to find a random grp.
hunter: no clue, don't play stealthers
sb: see hunter
runemaster: not sure, most people prefer warlocks or dark SMs nowadays, not a problem if you are rr7+ though.
spiritmaster: what can i say? dark will get you a grp easily, and you can solo very well anyway. supp spec(PBAE) is mostly for higher RRs.
bonedancer: great interrupter in FGs, but not really being looked for besides that.
warlock: king of tower/keepfights, gets a grp easily because arpees are almost always guaranteed. The problem might be 99% of mids have a warlock nowadays.
Valkyrie: even worse than thanes, though an ml10 warlord valk can really own hordes of stealthers in a duo/trio.