Big Tetris fan, i think you did a good job a getting the overall feel of the game. Though there are definitely some modern feature you could look on working on if you wanted to improve upon the game. Such as holding pieces, t-spins/other spins, 7-bag randomness, and hard drops. Also, maybe consider adding something to the game to set it apart from other Tetris, love it when developer put there own spin on old games.
Congrats on submitting a game. Hope you continue developing new projects!