Your game is cool, but not for me. I found myself fighting most of the enemies to get more HP. I can type quickly so I had over 100 HP and though "well I am going to win no matter what" then got bored and quit. A maximum HP could fix this. But also don't listen to me.
I don't know what the purple text is.
I don't know if the game lacks variety. It was not super fun though. I did lose interest quickly.
I do and don't think the visuals are too plan. I like how unique the game looks, but it is literally a spread sheet. If you want to add some flare I would say go for it. If you are happy with the way it looks then don't.