No other mmo out there really has a chance to do this but this game. The reason I'm suggesting this is because with the new version of ff14 coming out were going to lose people from ff11 for some time and it will make it easier to switch back an forth from the games.
DO NOT need to have it so we have gear we earn from both of the games or other such stuff.
Just have it so we got a NPC we can talk to that will teleport us to one game or the other.
Example: Im on ff11 and nothing happing and i see a shout or yell that there a group of people in port jueno looking for members in ff14 to do a run, i can just go to a NPC person and talk to the NPC and it will after a few, see that i got ff14 on my system that im using and just warp me to ff14. and can be vise versa.
Game all ready see that with the billing system that you got both version nowdays just all they need to do is detect got the one the games on the system your usinsg.
This will make it easier for those of us that would like to play both version of the game , and make it so some that like to play both versions of the game will pay you guys more and, No matter what there always going be downtimes on both game for updates and what no,t while the new contents added so why not make it so play both games same month?
PEACE.
If all think bad idea i'm sorry just felt like it makes sense do this instead of logging off and logging in all the time, and To make the game feel like a final fanstasy universe instead seperate games, plus give us options on the downtimes.