Even with the hidden extra difficulty levels, the whole thing feels like a easy-type version of Tetris Plus, taking into consideration that this one was arcade exclusive, and the player couldn't bang their head against any given puzzle until they broke through. A lot of levels can be cheesed with the two bombs you get per quarter, making the whole thing feel kind of pay-to-win (more so than most arcade games, that is). The scoring system doesn't really incentivize taking the more difficult paths anyway, but at least the branching paths offer some good replay value if you somehow have infinite credits (which really seems like the only way to play this one). The addition of the Assistant as a playable character is a positive, her increased speed mitigates the otherwise slow nature of moving a character you can't control, but can also be a liability, now that there are obstacles you have to neutralize by placing a block over them.
Worth a try, but it really highlights how ill-suited to this rotation system the entire concept of Tetris Plus' puzzle mode is. They need to bring the mode back under the modern Tetris rules.