I think this is one of the big questions the devs think about, at least I think they do, when they are designing CoT. There are a lot more answers to this than I want to discuss on this thread but I've been watching some 'Let's Play: City of Heroes" from years ago and the nostalgia was just...tangible. Looking past (or after?) the character creator to actual, in-game hooks that really got me were the variety of sound and color effects for powers and the animations for things like leveling up, finding 'clues', getting enhancements and inspirations, etc. I've never really seen anything like it in any other game. For example, my main in CoH was a defender solely created for being the healer. I loved it. Being in the middle of 7 other players, all of their power animations on top of all my GREEN! Man I loved those green animations for healing, even the sound animation for it.
Another part of CoH that I loved more than any other game's style was leveling. The in-game, level-up windows color scheme and design made them great, as well as the functionality of it. I noticed that while watching these old CoH streams when they would level up; specifically when you chose a new power it had this lightning sound and visual affect. Not sure why I like it so much...it somehow made it exciting.
Even the animations on getting new contact was cool and exciting for some reason, not sure why.
I have no choice but to have complete faith in our CoT devs. I don't know how they draw their inspiration for all the designing for CoT, but I hope they can mimick, not necessarily copy/paste, the animations to give us/me those same feelings.
All we have to decide is what to do with the time that is given us.