So much of this game seems to have changed, so if someone who is up to speed could give a rundown on the major differences between the brigand, assassin, ranger and swashbuckler it would be a major help to me, and I'm sure others.
well, from an RP perspective the class titles should be fairly intuitive - beyond that, all are considered to be great dps (assassins probably have the edge here overall, but its not a staggering amount.)
For dps consideration Brigands and swashbucklers typically go for 1h weapons due to an AA line which requires an empty offhand, with a 1h weapon
Rangers, obviously are ranged, assassins are the closest thing to the eq1 rogue imo.
Honestly though, what kind of character do you want to play? each of these classes has its merits, and is quite enjoyable to play.
Brigands and Swashies are more group utility classes imo, both get quite a few debuffing attacks and also a group-stealth called smuggle. Additionally, both Brigs and Swashies do consistent medium-dps - with their attacks being primarily light-dps, fast-reuse and medium-dps, medium-reuse - so they only realize their maximum potential during long fights.
Rangers have the most important attribute of rangers from EQ1: uselessness. They really don't solo very well at all, since 90% of their attacks are ranged and cannot be performed from close-range. And to top it off, in dungeons you really don't want to be standing back in ranged-attack range anyway, as a repop will quickly own you, yet without aggroing the rest of your group.
Assassin's deal extremely high burst damage, and are the best for short fights with their high-damage(but lengthy-reuse timer) attacks, they still perform admirably in long fights as well using their quicker-refreshing attacks again when they come up to keep their overall dps at a slightly higher level than either swashies or brigs can attain to. If the fight is long enough, an assassin may even be able to use his highest damage attacks a second time - giving the assassin a big margin on dps over swashies and brigands. Assassin's also solo the best of the non-bard scout classes imo: with the ability to simply obliterate an enemy with their most devastating attacks before taking any oticable damage. And they still have enough medium-dps, medium-reuse attacks to use so that an assassin played just right can chainkill solo mobs while taking minimal damage. The only real downside to an assassin is the lack of light-dps, fast-reuse attacks - which can potentially land you in trouble when soloing if you aren't careful and get yourself too many adds.
So, me personally, I'd go with the Assassin hands-down.
If you end up on Kithicor server as an assassin, do send tell or mail to Taeluuin or Astoroth(my berserker/weaponsmith and sk/armourer, respectivly) and we'll see about setting you up with a guild, some gear, some mentoring for the first few levels, and general game advice and information to help you get started up. Of course, that's only if you end up on Kithicor and Evil(Freeport/Neriak) - I don't associate with any of the goodygoody rabble by choice =p