I honestly had fun playing the game, my best score was 7195
It has nice arcade feel. For me the best strategy was to keep 3 soldiers so you won't get one shot and replace them quickly. Only bosses were a problem because you don't earn a lot of money to keep replacing soldiers.
The slow reload speed makes sense as it incetivises having more soldiers. I would like to have some small reaload bar for the soldiers so you know when will they be able to shoot. The camera perspective, moving enemies, the soldiers lagging a bit after the main one, it all made it rather difficult to reliably aim, especially with the non-center soldiers. Would be nice to have some kind of laser sights of their trajectories.