It's really well designed up until you're asking yourself why you play. PVP is great. It just lacked vision.
The castle sieges were all about camping bugged areas and pulling. It reminds me a lot of DAoC, which ironically is the same company that made the game. If they had different difficulty castles that fewer players could do, Alliance benefits (and bugs resolved), community events, and made each race's zones more unique, I think it'd have a lasting appeal. I'd go from one place to another, and it'd feel like the same POS ghetto town I just came from.
They needed more PVP only based Titles, Loot, and zones. The RvR was all about massing players and there was nothing a single person could do. They need like repeatable randomized quests that can only be done in RvR land, so you can actually earn Renown doing it and hunt other players down. Instead of having 12 RvR zones, they should've just had 4.
If they changed some things in the game around, it could be a lot better. They just went with what they've always done and didn't bother thinking too far ahead. In the same respect, others lost their interest as well.
When will they make an MMO where you can design your own animations, character looks, and skills/guilds? Now that'd be a game worth playing. Have players design parts of the game and hire moderators to confirm it's legit.