Thank you for the kind words, I'm so happy you liked it :) You're right in that it needed more to keep it engaging. Time was the cause for that unfortunately. I had a ton of ideas that I wanted to add but just didn't get round to in the end. I'm glad you still enjoyed it despite those missing features though :)
Good for you for making it to Wave 20 though, I tried but couldn't haha. The only thing that wave allows is for up to 3 X enemies at once, and also "extreme" type words that are around 10-12 letters long.