I don't understand you. In what sense can you make changes? Please explain.

You've essentially "diplomatically" acquired, for example, three hundred dwarves, then went to Utopia, placed them there, and in return received all the contents of Utopia... :D What's not clear about that? Or you can clear out the Angel's Lair, or the Wyverns... whichever is more convenient. ;) You can exchange them for experience at the altar, for resources at the Mercenary Guild, or turn them into skeletons at the Necropolis. That is, there are many ways to turn even troops that are not useful to you into something beneficial. And imagine when level 7 units join you in the first week...

And you say that diplomacy didn't help you... But did you actually use it, this diplomacy? :)