Class "needs" change all the time, as people with many alts log around on different chars. Usually there are rarely enough healers, but Destro often enough has good numbers of tanks. Again, this may change all the time. You should just play what you enjoy instead of somehow trying to play in order to fill other players demands.
Warnings on which classes newbies should avoid: Don't play Sorceress, you will kill yourself too much. Avoid choppa, another suicide career. In general, melee DPS requires higher skills than ranged in general, unless you really know what you doing and willing to learn through hundreds of brutal beatings. WE is lethal, but mostly naked, meaning once focused they drop fast. Marauder is solid choice and the backbone of any Destro meleetrain, and in general a really awesome class. Squig Herder is really good at the moment, Magus can also shine but might be a bit frustrating experience at times due to static pet mechanic.
Disciples of Khaines used to be the easy choice in the past, but after some nerfs the class is now quite the challenge due to never having enough Soul Essence to keep the heals going. Shaman is quite the annoying git, awesome mobility but somewhat weaker in the healing output and utility compared to the all around good healer Zealot.
As for tanks, Chosen is best due to sheer amount of easily available utility, followed my Black Orc who both dish out nice damage and buff up their groups. Blackguards look awesome and have nice ST debuffs, however, they are failures when it comes to playing a group support class, and can at best only buff one of their allies, which makes them the hardest Destro tank to master assuming you want to be a useful team member.
However, that's just my opinions, if you really want to succeed, you can do it on any class regardless of how steer the learning curve is on that one.
