Well, I just really like puzzle games and solitaire games, so this just fell right into my niche!
Yeah, wanting to avoid the bag system makes sense for what you described (same thoughts as what I called 'making it a solved game').
And yeah, very understandable to not want to open up the code again (for a variety of reasons). The different plane types would have made this much more interesting! Cause, theoretically, a perfect game would have you continuously getting the exact same tile every time, so having some variety of planes that act different to break that theoretical up could've been cool! Though, for what it's worth, the transition looks very smooth. For a game that you were making while learning the engine, this seems mighty impressive to me! Congrats for managing that!
Will definitely check out Urbion, thanks for the suggestion!