RTF is a global modification that replaces all towns in the game.

Good idea – by the way, the recruitment window in the alpha version of Heroes 5 was very interesting (in the alpha, I only saw the recruitment window for humans).
Some material could be taken from there.

Well, in principle, it's possible, if someone is proficient in GUI, you can replace the recruitment with the one that was in the alpha, but it's terribly inconvenient... especially with three tiers, I don't know why so many people like it...