I think that one of the resources that people run up against is available time. I know that is a limitation for myself.
One thing I need to do soon but it is hard to rip of the bandaid is that my clan doesn't clear NM or UNM. So I am losing out on chests. I will need to find a new one soon. I mean, I should not be the one putting out the most damage on NM.
All that aside, I don't think everyone should be able to get every fusion. Especially since they are often some of the best legendaries in the game. The game will get real old if everyone has the same champions and the same teams.
Another thing that I will add is that Fyr-gun is not a bad consolation prise. Even if you cannot pick up the fusion having two or three of her in your roster adds some fun and flexibility.