Hi there,
Artemis is actually one of the more populated servers but like all the other servers, there's not much of a lower level community. Like you said, the game is fun and I personally liked the story line behind the quests. However, most people these days usually hurry and level up because they want to run the end game instances.
As far as world chatting goes, there's not too much of that any more. It could be partially because of the cost but also because a lot of people don't tend to pug these days; something I wish there was a lot more of. You can however join the trade channels by simply typing /join Trade or /join trade. This is free to use and sometimes there's some activity in there. You were correct about the instance queue, no one uses that. Most people just world shout if they want to do a pug, or can zone shout for free.
It may seem lonely now, but like I said earlier, there are a lot more people that are in the higher levels; many of which that like to run the lvl 55 instances or higher. I've been playing for a little over 4 years now, and while I don't have time to play as much as I used to, I still enjoy it when I can.
Hope you decide to stay! and Good Luck!