I think the same ones can come at different times for everyone, depending on how/what you learned and what your personal chess "vocabulary" is (the way you personally conceptualize the play).
One young IM (I think Lendermen) said chess to him was all about space and tempo... he said every move was about one or the other... that was just his personal conceptualization of it at the time, probably from a revelation like your own where things suddenly make sense in a certain context that they didn't before.
Like tonydal said, as long as you keep improving, you're never going to stop having these sorts of realizations.
I remember certain things like that that I'd read or heard advice about all the time, and would have happily repeated it for you... but then one day it just hits me and I start actively using that advice during my own games.
My most recent "thing to remember" or revelation is preserving or ensuring my future prospects for play. Against strong players I can get shut down early in the middlegame in the area my play comes from (lets say the queenside) and against any kind of player I can reach an optically good position that has reached it's maximum.... I kind of think of it as a zero-point initiative. At best, you're equal and completely on the defensive... at worst you're just losing. All of this in spite of the fact that your pieces look active and your structure is solid.
Understanding the idea behind good bishops, bad bishops and opposite colored bishops helped improve my game.
Now I don't wait for the end game to start thinking about those things. I think about good bishops, bad bishops and opposite colored bishops even before I reach the middle game.
Are there any other chess epiphanies that a person at my level still might not have had?