Object rearrangement.

I acknowledged that it was a drawback, but it was a minor one. Restarting after a month is, of course, a bit much, but you can restart after a couple of weeks.

On large random maps, five weeks is a perfectly reasonable timeframe. Weeks 3-4.

It's a noob move, sorry for the expression. Normal people arrange the final battle when they meet head-on, not when they've gathered their troops.

Yes, yes, teach me how to play Heroes, "noob move" :)
The map is large, almost entirely open, so a treacherous attack is simply not possible. No one wants to attack first, as the path from their home city is long. Stalemate.
Should I abandon the game or try to negotiate and play a final battle on neutral territory under roughly equal conditions?

And on large maps, it's not difficult to research "Summon Troops" and "Portal to City" (I'm talking about the fifth installment).

Yes, brilliant! But here's the catch - to use them effectively, you don't need to capture any other castles on large maps.... otherwise, who are you going to summon from the nearest city of another race? ))))))))))))))

And in the third game, the portal to the city is so good that gathering an army will take only five minutes if you have "Fertile Lands", of course. But at the beginning of the game, you have to think and play with relatively small armies to maintain momentum,

Yes, the city portal, the dimension door, diplomacy with visions.... a brilliant trio, how can the sixth game with its mega-cheating, rebuildable cities compare? :)

instead of simply buying up all the growth in each captured castle.

I don't understand... I CAN'T seem to buy up "all the growth" in the first few weeks of the game in the sixth installment, while also rebuilding all the castles and dwellings. Even in the campaign. I only play on hard difficulty. What am I doing wrong, guru? Maybe there is a balance after all?

Added after 3 minutes

This is part of the game. And when you manage to win with a weak position, it's an incomparable feeling. Especially if it's in a tournament.

This is random. In card games, there is randomness (if you're not a cheater), but in chess, there isn't. And both are perfectly playable.