I think it ended in a perfect place, having grown up with it and noticed its somewhat-decline near its twilight (ha!), but also think that just because something is "over" does not mean you have to "move on". These are very loaded terms that imply there's a correct, optimal option to take when a series ends. There really isn't.
I wouldn't be here without G4 either. It gave me meaning, purpose, and community. While my sense of community has been somewhat shaken over the past few years, the meaning and purpose still remain and are a core part of who I am. I don't think I'd ever have challenged my identity if I hadn't learned to do so through the show and community.
I also wouldn't be here without G5. Just when I was starting to lose hope, just when I knew I could never move past FiM, just when I thought I couldn't take anymore fandom drama...I rewatched both G5 series and found a new pony love, new values to adhere to, new characters to love, a new world to build. Though a great deal of people disagree with me in finding anything of value in what we got (aside from the movie, which is universally at least "pretty bang-up good"), it's only important what I get out of this new iteration and community...not what others don't get, or what others put others down for possessing.
The fandom itself might fade, but that doesn't mean you have to. Continue to produce, talk, engage, discuss, and enjoy. Just because others have moved on to other things doesn't mean that you have to. You will always be welcome with those who come later to experience what you were there for.