After playing alpha (please note things are 100x better now) I'll say this: (Read ALL of it to get an understanding because it feels like you skimmed)
~ Card System is fine the way it is, it makes things unique, and varying.
~ Pet System is unique. Think of the 100's of mobs there are in game... and being able to get a pet version of each of them. Their not purely aesthetic either. They boost stats and also had the ability to level and use skills based on the client data.
~ Life Class System - I've played EVERY mmorpg listed on OnRPG's list, not one was missed, unless it got shutdown. I've also played LO. I hate crafting, and I play through games with minimal to no crafting. In LO, thats totally different and is core game play, ofcourse if your rich you don't need to ever craft, some people crafted their way to max level as a level 50 life class.
Theres SO much you can do with your life class, even in the future you can build buildings and identify unique items that others would not be able to because of their low life class level. The extensiveness and etc, I have never seen in any game. Yes I've seen similiar things, but most definetly not to this extent, and yes I've seen GW2, i have many guildies playing it and totally understand it
~ Couple System - Believe it or not, male:male , female:female relationships exist in game ya know, even if its for fun or just the boosts that you may get, its not super extensive in LO yet from what I know, but its there unlike many MMO's
~ Quests - Although i highly doubt it will have dynamic questing, but heck LO is F2P! And the quests are very rich in story and plot. Not to mention the game is very quest based as opposed to grind based. But if you dislike quests, they generously offer an extensive party system to allow for easy leveling in parties. As a note though, LO does vary up quests a bit instead of just the average "collect x and give to npc z", there are quests that involve finding objects and using them, and having the objects summon mini-bosses, etc. etc. However Life Class quests are fairly the same, they involve crafting an item and giving it to the npc, but crafting in itself is a fun journey.
~ Dungeons - Now this might interest you. There are 2 different types of dungeons in LO. There should also be raid dungeons, but since I don't have info on that, I wont say anything.
- Party Instance Dungeons - These dungeons are in an instanced zone, offering multiple modes of play including easy/hard/etc. They come with a final boss and mini-bosses, all of which are an actual CHALLENGE, instead of the average tank-n-spank, they usually involve you moving around a lot. The dungeons themselves also involve traps and platforming! The dungeon is timed as well.
- Open Instance Dungeon - These are open to all players, and not just parties, you can see everyone in here, and they also have bosses. Not too much more is known. I've been in one and fought the boss before too.
- Raid Dungeons - Not much info.