Hello Gonzoman,
I know you wrote this 1 month ago but still i'm going to reply in case anyone else is asking himself the same questions,
1 - I'll be honest. The population in the EU area is quite sad. GOA hasn't done a good job managing DAoC, and the result has been the death of the English / Spanish and Italian servers. If you are French or German you'll still find crowded servers, but imho, the whole thing looks quite decadent.
However, I won't say the same about US. Under my point of view, the US servers have got a loyal & well established community, which looks far more healthier. You don't have the feeling of playing a terminal game there. Of course you can't compare the populations to the good old days, but there are still tons of great battles going on and even Mythic was planning to release an "Origins" server which i'm sure that would attract the attention of a lot of the old school players.
2 - When you pick a race and a class firstly you must "inspect yourself". A vital point about enjoying your character is to feel represented with it, in some way or another. If you have some free time take a minute the visit camelotherald.com , read some lore and read about all the races and classes, and then choose the one that fits your personality & gameplay style!
About soloing... I've heard that Necromancers master that art ;)
3 - Your best ally in your startup will be Patience. Camelot is old, but still has much to offer. However, you won't see the game in it's full splendor until you are a well-geared and veteran level 50 (Something that shouldn't take you too much ;)) so don't loose your hopes in the beggining. As a newcomer you may have a rough beggining and probably will feel quite lost and displaced, but trust me, that's just temporary.
About "material" tips... Whenever you log in game type /realms. You'll see a window with a list of the keeps and in the last line you'll see the realm that owns "Darkness Falls". Only the realm with more keeps in it's possession has access to that dungeon. There you'll find very good camps, money, exp and "Seals". There are different kinds of seals depending on the level of the monster. Those seals can be exchanged in the same dungeon for a very nice gear.
Hope this helps someone out there :) Take care all.