I personally feel that a lot of the '90s console JRPGS had the best stories hands down. I think what's lacking today is a great and original story. Back in the day you read everything and it gave a sense of immersion. There was more imagination involved. You were more engaged. Not everything has to be done with void acting, it's just become the standard. I'm not against that by any means, but it's overly used in games. Allow the player to think and decide how these characters would play out in there minds. Keep them constantly asking questions and of course, have it realistic as for how they would "progress". Very slow, gradual and to where you felt you earned the "level up". Or, felt you busted your ass for that 1+ skill point in archery. Don't hold the players hands let them figure it out.
Include a big enough world to explore, ton's of quests, and each level "bracket" really felt unique, not like "oh just 10 more levels now". Hell have small raids for those level brackets, so the game isn't just about the "end game", have every bit of worth playing. Thus, increase the longevity of the game. Each level bracket, would have an epic quest line to follow, with dungeons, maybe even some pvp, and a difficult raid, to "pass" onto the next level bracket. Its not about endgame, make it to where a hard ass level 40 helm is compared to a good level60 helm. Based off of stats of course. Diabo 2ish. Make items feel rare and powerful, one of a kind. A mixture of elder scrolls, "secret guilds", and if you're a member you can secretly invite whomever to your guild. But invites only.
Player driven and community driven. In game politics, if you want to be a guard , or knight be it. Be the authority figures, or be a thieve, or a summoner, or mage, or archer and the story goes through the community and is not so focused on the main (raid) storyline. Thrown in rare once ina while community events where you work together to open up a raid(AQ), or a huge pvp war, between all factions, driven by GAME MASTERS, to set themin motion. Just some very high ideas of mine.