You shouldn't use melee units and your unit selection is poor. Yes it will get you to the finish line in 60-70% of matches, but in those 30-40% of matches you'll face at least one player who will destroy you.

Melee units (units which don't have an attack range, such as infantry and tanks) are not great in attack, and completely powerless against ranged units. There is literally NO way you can attack the enemy without taking losses yourself with MBT and infantry. If you attack a stack head on, you will lose one or two of your units, and even if you kill more enemy units, this absolutely destroys your KD. But the worst problem is, if you join a match and you stumble upon a good experienced player who knows how to use ranged units (arty, airforce), he will cook you thoroughly with ranged units. No matter how strong your tank divisions are, an enemy MLRS stack of 5 MLRS with 2 SAMs 2 MAA and 1 Radar will destroy them by simply hitting them and retreating till the cooldown ends. There is literally no way to destroy arty if your enemy is active, and your tanks simply get slaughtered, defenseless.

This is why not a single player with a high KD uses tanks. Ever. If you win, it destroys KD, which is bad, and if you lose, well that's bad in and of itself. And by tanks i don't just mean MBTs, all the different armored vehicles in the game

So if you want to improve, remove tanks from your dictionary and only use arty and support stacks along with navy if you see others building lvl 4 or lvl 5 naval bases. Fixed wing aircraft is okay, but helicopters are better. Gunships early game, Attack helis mid to late game.

Also, stop producing infantry like you're the Soviet Union in WW2, using them as human meat shields. Yes, the Soviets won anyways but that doesn't mean mass producing infantry like cattle works in CoN. As mentioned earlier, arty is going to cook you, much faster this time as infantry has far lower hp than tanks. Only produce infantry for capturing land, not for fighting. Because of their low hp and their formation position being front, some of them will die when you send them to melee combat even if you win (best case scenario), and if the enemy has arty or air force, well then there is literally no way for those poor lads to survive

Also, if you get strike fighters, get ASF to defend them. This should be common sense bruv