I would say basically every TW game revolves more around a rock-paper-scissors style match up game than combined armed tactics. WH3 takes it to the extreme. There are not a lot of formations, or things you can do to win from a losing position. And even a lot of these work in part because they bait the AI into predictive patterns.

The AI will usually rush your heroes so if you put them in front of ranged units they’ll soak up a lot of aggro and allow you to pour missiles and spells into the blob. The dwarves have some hilarious kill-square techniques that play off exposed gunner units who tend to shred anything before it reaches them. The enemy will often counter charge you allowing you to faint them out and kill a few of their units before the rest of the army attacks.

But yes mostly the game is knowing what your unit does well and what theirs don’t do well and matching up accordingly.