I've been playing the same game for around 20 days and I feel I could go on forever, even taking some risks sometimes. I've never been able to do more than an around 30 times streak, and in all situations I could not continue the streak I think I was in situation where there was no way to continue with just one move (even if a shift move). I don't feel the energy limit challenging at this point.
Maybe there could be different modes:
- Zen: the current game without energy.
- Streak: just one strek, game ends when streak ends.
- Puzzle: also just one streak, the placement of new pieces is not totally random and are guaranteed to let you continue the streak in one move (or maybe two, which would make the puzzle more complex?)