That's definitely one of the options. I think, so far, it's CyanogenMod, Paranoid Android, Replicant, Sailfish OS or Firefox OS. My problem with the Android variants is that they're vulnerable to Google; if Google decided, for instance, to move really core functions into Play Services, they could make these variants unviable. Also, after-market OS's have never been popular, and you want to put your weight behind something which might actually be sold in shops, and stands a decent chance of gaining significant market share and momentum.

You're right, though, that I'm being a bit overdramatic, the options are definitely there.