I haven’t played seriously in about ten years. Every now and then I stop back and see if I can see a reason to play. I tell you what isn’t a reason, plex and subscriptions.
Most of what my character can do and fly is locked behind the pay wall. So I get some T1 frigatte, put about a little and pretty soon I’d rather be flying Elite Dangerous where I have all my stuff, where the planets actually orbit and where I can get out of my space ship and do interesting things.
Most notably where I don’t have to drop a dime to play, but where I regularly spend money on cosmetics because they are awesome.
I left EVE when walking in stations died. Ten years later it’s still a forgotten dream.
So, you want to see old players back? Change your free to play system. Remove the locks on content, let me have all my skill points. Don’t let me train new ones. I don’t need them. If I do want to skill in some new kind of ship, if there are any, then I’ll slap some dollars on your barrel head, but I’m more likely to care about a cool skin for my Archon if I can fly my Archon. As is, there is no reason for me to purchase anything.
Give the people paying you a little something extra, a better loot table, or a boost to ISK or a discount on ISK fees for their citizenship status.
You aren’t going to get me to want to play locking my toys away, I’ve lived without them for ten years. You get me back by letting me have them and showing me there is something cool to do with them I can’t get anywhere else.
Heck even if I had to drop like $20, or $30, once, and once only, I’d probably call that a draw. I can eat McDonalds one less time. At $15 a month, or whatever you charge, you are competing with HBO and Netflix and their subscription offers more than yours does.