My name’s Siobhan and I’m a soloer and a serial alt-slut. I’ve played WoW, CoH/V and GW*. In the end I keep going back to WoW.
GW is good for pure soloing, it’s a pretty game and it’s fun in its own way. But IMHO it’s a lot more repetitive than both CoH and WoW. Your character choices are more limited, and they’re all human. Regardless of what class you choose (2ndary or primary) all characters start in the same area, and even with alts you find yourself doing the same quests over and over again. The level cap is quite low, so you run out of things to strive for after a while. The biggest selling point for it is no ongoing monthly fees. You pays your money for the game and that’s it. You don’t need a CC or anything to run the account.
I agree with Oakminster’s description of CoH/V. It’s the perfect game if you’re wanting to solo, but you occasionally get the urge to group or PvP. Before CoV, I found that the game was pretty repetitive with 99% of the missions being “Go into this cave/office building and kill x amount of y character, then report back. Once you’ve done this z amount of times, go back to that cave/office building and kill yon boss creature”. There was the occasional escort mission and not much else. CoV has increased the scope of the missions immensely, adding new enemies, locales and mission objectives. But even now after a while it can still get same-y, with all classes again starting in the same areas and going through the same low level missions against the same bosses each time you try a new alt. But there’s a lot of good players in the game, and the classes are all pretty fun to try. For sci-fi/comic geeks it’s a pretty neat game.
WoW is the one that keeps dragging me back, however. I like the range of character races and classes, as well as the skills you can learn (gathering skills like herbalism and mining, production skills like tailoring and engineering, all around useful skills like first aid [yay healing!], cooking and fishing [yay food!]). There’s faction and class specific quests, so even if you’re playing a human paladin and a human warlock, or a tauren druid and a night elf druid, you’re not just going over the same quests in a different skin. There’s a player-driven economy based around the auction houses - you can play the auction house, buying cheap gear and selling at a markup in order to earn more gold and thus buy better stuff. If you want to PvP, there’s PvP dedicated servers where you’re taking your life into your hands every time you leave your faction cities, or there’s PvE servers, where you are safe no matter where you go, but you can turn on your PvP flag or go into a PvP battleground whenever you feel like pwning some n00b beyotches.
PuGs (pick up groups) can be a bit hit-and-miss, but if you find a group of people you like you can friend them, or join their guild. Even in a guild you aren’t obligated to play with others. You can just sit in guild chat razzing people up while you solo your quests, and yell for help if you need it.
All 3 are good games, they’ve got good and bad points. CoH and WoW both offer free trials, so if you’re looking to try something but not be bound into buying anything or signing up for any ongoing costs, check around and see if you can get yourself into a trial. If you don’t like 'em, then you’re not out anything more than a few hours time.
*I’ve also played EVE online and Anarchy Online, but neither of those to the extent that I’ve played the first 3.