[Scrumtick]

If you want to avoid classes that are somewhat gear dependent and beyond your means, avoid tank classes and, to some extent, melee classes. My first was a monk. The lacking of funds for high-end gear frustrated me at times, but it wasn't too much of a hindrance. This would probably be the same for rogues and rangers. You can get by with minimal gear, but they really shine if you can dump some money into them.

I would also avoid shaman as a first toon because their level 50+ spells can be extremely expensive.

That would leave druid, cleric, intelligence casters (enchanter, magician, necromancer and wizard) and bard.

Now you also have to consider ease of play, play style and whether you plan to use the character 50+ and for raiding.

In terms of ease to play, you can't go wrong with druid, cleric, magician, wizard and necromancer. Bard and enchanters definitely require the most learning.

In terms of play style, all of the intelligence casters can solo to some extent while druids and bards can easily solo. Clerics are definitely group dependent for the most part.

In terms of 50+ and raiding, enchanters and bards are in massive demand because of their buffs and crowd control. This is also the case for clerics since they are the best healers. Then there is a gradual decline in demand for the others with druids probably at the bottom. My 55+ groups almost never take druids and are often hesitant to take necros, wizards and mages (although, personally, I think they are fine in groups).

TLDR: can't go wrong with a cleric (best heals, easy to play) or bard or enchanter. These are always in high demand even if there are a lot on the server. However, if there is a specific class that has peaked your interest, just go with that one!