I think getting players through a full run shouldn't be an issue, but the game currently lacks some long-term motivation—since enemy variety, build diversity, other gameplay elements, and map art are still fairly limited at this stage. I think a decent reference might be the trailer for Echo Generation—it showcases a range of different themes and monster designs.
Thank you for the feedback on the game. It's still quite rough and unpolished at the moment. I did originally plan to add more tutorials, cards, and enemies, but in the short term, I just wanted to make it look presentable enough so I could show it to others as a rough demonstration.