Diplomacy, for recruiting creatures of levels 1 and 2.

And where can you find a lot of creatures of level 1 or 2? Even a gold mine rarely has creatures of level 1 or 2 guarding it; such a change wouldn't unbalance the game.

Almost everywhere.
8mm6a:
Zone contents:
1-8, 15, 16, 19-22, 25, 26 - 500-3000 (9), 3000-6000 (6), 10000-15000 (1)
1. That is, out of 16 guards, 9 will have a value of 500-3000. Well, maybe a 3k value can generate a level 3 creature with -50% stats, but more than half of the starting spawn consists of level 1-2 guards. (here, 90% of the guards are level 1-2)
2. 16 out of 26 zones have this type (and 10 of them are treasure zones, and some treasure zones are smaller in size!!)
Treasure zones also have a 5% chance of containing some kind of Greater Cerberus.
I won't explain the rest of the patterns, but the picture is similar, and it's obvious to other players because they play and are familiar with the game.