As always it's a high quality, highly polished game with great graphics and awesome music by Facemeltingsolos; and add interesting story as a bonus -- amazing job.
I must say though I thought TD x Card were something new but I just realized that... PvZ is TD x Card isn't it lol damn it XD
Gameplay wise though... I think playing your game I realized exactly why most TD games have wave system and are usually way, way more slow-paced than this. I guess with the fast pace this game has I was given little time to think; though luckily the game balance is somewhat in the favor of the player so mostly I could do whatever I wanted and still win; except for the boss stages I suppose where I needed to put some decoys -- very commendable design decision.
With some tweakings and maybe let's see... making the cards unlockable let's say so that it's not so overwhelming at first (a more introductory stage would be nice)... I think this has got some potential to become a bigger game.