I like the idea and the art is fun. When I first played the game I had very little idea what to do - and reading the initial description only helped over so slightly. I had to go read the full description to figure out that the number under the people in the bottom was their wallets, and that they were the customers that you'd send down the road to destroy the towers - and that turning those customers into knights and rangers etc. gave you their money (and if they're short you pay the rest).
After I learned that, the game became very easy. So easy that I could probably never lose because there didn't seem to be an increase in difficulty over time.
And without reading the game description I'd probably never have guessed that the lose condition was getting too many towers present.
There were some conflicting mechanics though. The passive sales seemed to work against you - it cost me time and at best it'd get me slightly more money than just buying the weapon that was currently closest to their wallet's contents - and at worst it'd make me break even but with a "loan" from the customer while delaying their aid with tower-weeding and keeping new customers from coming in.
Also, constantly clicking back and forth was a bit hard on my wrists and seemed unnecessary. I'd have appreciated if we could at least press 1 through 7 to select customers.
Screenshots from my playthrough: https://imgur.com/a/GrmuiD3