I totally agree about it getting boring after you lose heads. The gameplay shift was meant to make it more intense for the remaining lanes, but it ends up being a laser spam fest until the rate of evil head spawns becomes overwhelming (which it technically does, because they'll spawn too fast for the laser recharge time to deal with). Being able to move remaining heads between lanes is an interesting idea! Could make the game feel more like a an actual bullet hell at that point (a somewhat more railroaded, onto 4 tracks, kinda bullet hell).
I likely spent more time on those graphics and remixing the backing track than I did on refining core gameplay D: thanks though! And thanks for playing and the feature in your video! :D