I have played many games throughout my life. The most memorable ones tell a story, and provide a new world that you get to experience through the characters of the game. They provide interesting things to accomplish and test your skills in a variety of ways. The same game mechanic can be used over and over but people will play the game just because it provides a different narration.
Take for example Mass Effect 3, the whole system revolves around selecting a mission, go kill some guys, then rinse and repeat. There isn't a whole lot that changes, and there doesn't need to be. Because as the narration changes people are willing to repeat the process. While eventually that gets old, people will stick through till the end.
With Eve Online there is a vast galaxy to explore and build upon. It advertises itself as a sandbox environment where you get to create something of yourself. There is a lot of stuff that one can do. It holds a little bit of everything, an environment to enjoy the concept of internet spaceships.
There is a huge misconception to a very vocal aspect of the Eve player base. Their basic ideal comes down to "Eve Online is solely a PvP game and if people don't want to participate they should quit", this is quite erroneous as one can easily look at the opportunities provided and see there are quite a few things that don't involve PvP. (I'm not saying PvP can't happen, but it isn't necessarily the intent of the activity.)
There is a large and vast opportunity in Eve to produce a lot of content for players to do either alone or with others which doesn't involve them trying to kill each other. In my opinion it doesn't even need to be complicated or ground breaking. Take for example the missions that are available. You get plenty of people who will rush through and not even bother reading the text. They just want to know the objective and then complete, receive reward. Others enjoy reading things, it isn't all about making the most ISK per hour.
According to EVE-Survival I counted 483 missions, ignoring the variation of the level. That is quite a few, and I haven't experienced all of them. But when I do missions and I end up getting the same mission three times in one day it starts to get old.
You don't necessarily need to change the mechanics to revitalize something. (Look at Mass Effect 3) You could squeeze in a couple of new mission ideas in an update or expansion or even introduce more epic story arcs, dynamic events could even be incorporated. The universe changes, but how come the missions never do?
To give a little perspective, World of Warcraft has over 10,000 quests that one can complete. Does this mean Eve needs to have 10,000 missions? Nope, but it sure could use some variation. CCP has started on that a little bit with the Odyssey expansion by doing a revamp of how exploration works and the redistribution of resources. But as far as I can tell so far, there is no addition of new missions.
From what I understand, the only places ISK can come from are NPC's through bounties, or completing missions. So someone has to do some sort of PvE activity for more ISK to be added to the system.
Shouldn't that activity be enjoyable?