The quality is good.
Feels a little "on the rails" though, just 'click the upgrades as they become available' since there are no micromanaging involved, just keep runs running until you you can afford an ugrade.
At section 9 all the death and shooting and fighting sound become super choppy.
If future gameplay will stay like that i'd say "i've seen enough of this game to know where this is going". Not super interesting.
Allowing to suggest the army a dirrection to hold or a mechanic to make them get into a formation, like close for swarms, injured to the back, and spread out fo aoe big enemies would be fun and allow to funnel enemies towards a more uniform warriors with the low hp boosts.
Good game but the sound needs fixing.