>>12129386
It's good. It has campaign mode where you keep units between missions and they level up. A lot of units can be promoted to special variations once they reach S rank.
There is balance in that you can only have 50 units. So you have to choose your 50 units carefully. There's five different helicopters, attack, attack+, transport, transport+ and anti-sea. The "+" variants aren't 100% better, they are trade-offs. That said a lot of maps in campaign are relatively easy once you figure out how to play and get your 50 units.. except for the last few maps.... but it is a kid's game after all.
In terms of sea units with anti-air, there are two sizes of carrier and they both have ranged and direct anti air. There's also a "mercenary" frigate that has long range anti-air as well as an anti-city gun. Another important one is the "Aegis Warship", which has ranged anti-sea. The mix of units is good, it gives a lot of flexibility in terms of how to finish maps. I don't find that there is a paper scissors rock aspect, more so there's a priority... like, I'm not going to deploy any carriers while there are submarines in the water, first I take out the subs with my subs, then I deploy other ships... similarly, I'm not going to deploy vulnerable air units while there are fighters or interceptors in the air (there's also the "attacker" jet which is like a multirole that does air-to-air and air-to-ground).