To me, certain character limits tend to be problematic not because of the length of actual content, but because of formatting tags and embedding taking up a lot of characters. This is something I experience on most of websites, not just this one, but the most aggravating issue over here is linking to user profiiles and other sources of strategies, which could be alleviated with internalisation of link paths and @mentions.
Only really to expand on Gráinne's comment as regards the 'collecting' and 'roster development' sections - which are, as said 'distinct' although they are intrinsically linked - I would like to point you in the direction of the in-game Achievements > Battle Pets > Collect tab. There are a series of achievements called Raiding With Leashes, pretty much all of which can be completed via the auction house - if you have the gold/inclination - or by completing old raids.
In Classic, playing different classes actually feels different in more ways than just their abilities, at least if you think about it a little. Playing a priest, you really want to find a group because that's what the class was designed for, which is both good and bad - you're stuck very slowly leveling if you're solo, emphasizing the frustration of the slow pulling, but having different classes require different gameplay can be good. If you want to play a priest you're going to have to be more social by default, just whisper the guy you see killing stuff next to you and go level together, you'll immediately have a better time of it (this part is particularly exacerbated in the beta, as there are fewer players).
It is a great advantage to start making some silver and your first gold coin at low levels already. Skinning is a nice choice here. Fast and easy way to gather resources, leather of all kinds while leveling for those who are at the race to level 60. There are many good spots to grind beast mobs and skin them. I like doing it as a Troll Hunter, trolls have a passive racial ability: + 5% bonus damage against beasts.
Druid is one of the most versatile classes across all of World of Warcraft Classic. By picking Druid you will have plenty of options to choose from while leveling. However, in the end-game, most groups will expect you to heal, though, Feral and Balance druids are also very desirable for their Innervate and Rebirth abilities. Additionally, various animal forms will make traversing the world into quite an uncomplicated task.