This game definitely is fun, but there is a definite need for tooltips. I have no idea what the reward for Recon mode is (I see a bar that goes down each round, but no idea how it fills up), or what the percentages under the Troops section means. I also have no way to figure out why Overkill isn't working in Recon mode, or what the Recruit multiplier does.
Understanding the mechanics is a very big part of what makes games like these fun to play, so when seemingly important things aren't explained, it makes it hard to find a reason to grind.