MMOs run the gamut of playstyle and quality, so it is kind of hard to recommend them. Especially since qualities like "moneybrug" or "ghosttowns" can be very subjective. We only get out of it what we put into it. I'd probably still be playing EQ1 if I had people to play it with, but these days I play MMOs purely and intentionally to waste my time; I have no intention of making or maintaining any kind of social connection in them anymore.
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I've been playing EQ2. I don't know why, really. The TLE (time-locked expansion) server is fairly active at all hours of the day (helps that there is only one server so both US and EU play on the same one), for nearly ever tier of content (whether low level dungeons or end-game content), in every role (even classes that straight only pretty much DPS). Not many people group up for the non-dungeon group quests, though, but you might have luck if you join a large guild: even high level players might be willing to help for the AA experience (at the moment, on TLE, AA only comes from questing/named/exploration/other 'discoveries', instead of directly from experience, which will come with a later expansion). But maybe that's a moneygrub, since it requires a subscription? You could play on the regular servers: all content there is unlocked up to the most recent expansion, but there are some limitations for freebies (50% of your experience goes to AA, which can be a good thing depending on how much you don't want to rush through content). It's a pretty bog-standard themepark MMO, but they went overboard (way overboard, in my opinion) with how many abilities classes get.
Once I get bored of EQ2 I plan to try RIFT again. Another themepark MMO, this one parallels WoW more closely (ability/talent descriptions lift the format almost directly from WoW). A hell of a lot of it is unlocked for freepers, but I think it eventually requires buying expansions for content, plus some exclusive souls (classes/talent specs) separately. Not sure how its population is actually doing, though. (Also, I went looking around about it forum-wise and apparently there are obnoxious paywalls everywhere now. I planned to sub anyway but that may not be your thing.)
LOTRO is another fall back of mine, but it definitely requires expansions for anything outside the vanilla release. These expansions are available via time rather than cash by farming Turbine Points through deeds, but it is very, very time-consuming. Might make more sense to buy the expansion directly (I got all five for $25 during Christmas sales), as this also bumps you up to "premium" which offers some modest benefits over free players (who could otherwise buy those with turbine points). VIP/sub gives you access to everything outside of expansion content for the duration of the sub, plus 500TP monthly. All that said, the actual gameplay of the game never felt smooth to me. It's very stiff compared to other MMOs in its generation.