1. Performance on a Wide Range of PCs
One of the biggest reasons World of Warcraft is so successful is because it can run on just about any PC out there that came out since 2004. Not everyone can afford 600 dollar video cards and 8gb of ram and Blizzard knew this right from the start. This doesn't mean the game can't look great, just make it very scalable. The more PCs a game can run on, the more potential customers.
2. Grouping Is Not Always The Way to Go
I have seen so many MMOs out there that try to force you to group with other players for everything. I hate to say this but despite the 2 M's in MMORPG standing for Massively and Multiplayer, people love the ability to tackle things solo as well. I hate to cite World of Warcraft again but they are very successful because they cater to not just the social butterflies but to the loners as well. Like I said earlier, the more people you cater too the bigger your potential customer base. This doesn't mean you have to make the entire game soloabe. This just means that, espeically for leveling, do not force people to group. Give them options. Give them ways to progress buth during leveling and at endgame that are friendly to both groupies and soloers.
3. Progression
There were some MMO's that came out that could have been amazing had they allowed players to progress a little bit easier. While I don't expect to hit max level in a day or even a week I woud like to at least feel like there is an end in sight. Now being an older MMO player I know that leveling is way faster than it used to be. I remember taking almost 3 months to get to max level in original EQ. However lets face it, EQ svcks by todays standards, and anyone still playing it doing so simply because they fear change, can't play anything else, or simply refuse to leave all their work.
4. Endgame
Just because a player hits max level this doesn't mean its time to throw in the towel, and too many mmo's don't understand this concept. They think that little or no endgame content is ok because players will "just level alts". This just isn't the case. When I get to the max level you better be darned sure theres things waiting for me to do, or I will be cancelling and moving on before long. Too many games out there were great during the leveling process but then fell apart at the endgame. This doesn't mean every game needs to follow the strategy of instance/gear/harder instance/gear/raid/gear/harder raid/gear that WoW does. Be creative, there are solutions.
5. PvP
This is the one topic I can't speak much about because I really and truly can't stand it. I will say this though. DO NOT FORCE IT ON PEOPLE OR YOUR GAME WILL FAIL. To many games have tried to force players into pvpo in one way or another and for the vast amount of people that hate it you are forcing them to play something they don't want to. This is a recipe for disaster. One more time I will use WoW as an example. This is one game that does pvp right. It is entirely optional, but very satisfying for those that choose it.
6. Launch
The launch of a new mmo can literally be the make it or break it point. If a game is released extremely buggy and missing half it's features people are not going to give it a second look. Final Fantasy 14 is a perfect example of this. That could've been agreat game if it was actually working right. People do not care if you will have that new feature up and running in a later patch or that game crashing bug patched 3 weeks down the road, they will be gone by then and you have just lost money. On this same subject, if you release a game before it is ready, especially in this genre, it will fail. Plain and simple. I cannot express this point clear enough.
7. Advertising
It doesn't matter how good your game is if people don't know it exists. You cannot rely simply on word of mouth for a game to spread. You need to be in people faces with it, constantly. Word of mouth is a powerful thing, but so is having that advertisemant during your favorite television show and on your morning homepage. Many great game has failed simply because it wasn't advertised.
8. Standing Out In the Crowd
Any new game coming out in this genre is going to have to be different toeven put a dent into the behemoth that is WoW. Not to mention the bajillion other mmorpgs that have come out. This game has one thing going for it already, it is Fallout. Use this, build on it. Make this game feel like Fallout and not some cookie cutter mmorpg that takes a 10 year old game model and changes a few things. You have the tools now use them.
These are the main things I can think of off the top of my head. If you guys can just keep these few points in mind when making this game you will succeed. I guarantee it. I also want to throw out that I am an experienced beta tester with very good bug hunting and reporting skills, and I would love a chance to test this one. Hint hint lol..... Seriously though guys I can't wait to see what you come up with!!