As mentioned above, pinball is a hobby with natural ebb and flow. However there are ways to extend and expand the interest level aside from simply cycling new pins.
Pinball is most like the classic car hobby. You can fix them up in your garage by yourself which is rewarding enough but static. Kick up the interest level a notch by networking with local collectors who can share your appreciation, contribute tips, and provide help. Further still, you can enter tournaments as another way to drive your interest level even higher to "be the best" and win. It's the same with pinball.
Right now, in my opinion, the killer app most needed in pinball (particularly EM's) is high score tables and social media integration. We desperately need a way for people who aren't tourney-heads to get a taste of that competitive bug and easily share the joy with others. Sure, you can snap a photo of the game and post it to your Facebook feed... but it wouldn't it be better if the game itself could accomplish that for you and start conversations?
The Maker movement (Ben Heck, etc.) and groups like Multimorphic, FAST Pinball, and Mission Pinball are turning the hobby into an open-ended experimentation and art platform... which is the key to blowing the doors open to new possibilities and ever-higher levels of engagement.
As always, moderation is key. When it is time... walk away rather than sell out. You'll be back eventually.