I think if battery technology has a huge breakthrough before the next big energy tech breakthrough then solar becomes essentially one form of near zero point energy and continues to explode because then even if something like mini-coldfusion household powerplants comes on the market solar my still be the cheaper option by then if solar tech, like say our 3D cell, keeps evolving.
Battery storage of solar to me is the X factor. And Musk is working hard to research and make the next breakthrough battery both for his Solarcity panels and his Tesla cars and that gigantic battery factory he's making.
And the battery company that's very interesting to me the one Volks just bought a 5% stake in, QuantumScape, which is a small under the radar battery company which may already have a breakthrough battery:
Looks like they are trying to leapfrog Tesla. If QuantumScape is legit then Elon Musk has a whole new problem to worry about, not sure how that guy sleeps.
And this race for the best battery only helps solar because its all battery storage.
I think you made a good decision either way on getting the panels because like you said you're saving now, you have equity, and battery tech improvements could make your panels worth more in the future.