Play as Inferno.

Against various shooters and various mages (referring to neutral sorcerers):
- on week 1, only gating ones, but it's better not to mess with mages at all :D;
- on weeks 2-3 - gating+BDP+raise dead+machines with a first aid kit, and you can use seductresses (though it's not certain they will go in first);
- on week 4, everything mentioned above in various combinations+darkness.
Regarding the Dragon Utopia: BDP+raise dead+darkness, machines are basically no longer relevant...
And probably there is no need to remind you that in any case you need a mark in different variations (depending on the number of days passed since the start of the game and level-ups) with double damage or weakness.
As an additional advantage for dispelling, we level up keen mind.

Demons are almost a doubled army! Doubled! Mass spells are needed, the army will do everything.
The hero's first three moves decide everything. The hero's first two moves are Mass Stone Skin and Haste. Everyone except necros obeys succubi. WHY on earth is darkness needed in such a layout, please tell me?

And how are you going to replenish losses? Does it turn out that while you are casting mass buffs, the neutrals are just snacking? No, they'll be snacking on yours...

3. About utopia
To hell with utopia for the sake of 2 artifacts. In the late game, you can often buy what you need from the merchant.

Well, you are greatly mistaken here... Firstly, where do you get so much gold to buy the necessary artifacts depending on the opponent's faction? Secondly, there aren't 48 items put up for sale in the guild, only 6. Thirdly, it is far from certain that the artifacts you specifically need will be there. Fourthly, besides artifacts, the Dragon Utopia gives you experience, gold, and spells (though not always the necessary ones).

Well if needed - protection is required and I only put devils and spawn on the field. Level 2s are also possible.
Keep in mind that my defense, luck, and often attack are leveled up, and as a rule, I already have some artifacts for all this
But generally, in the late game, I move with a hero who has one empty slot for a squad, waiting for joins, and then I throw this joined squad forward into utopia. Otherwise, I don't really go in...

Spawn or lords depending on which neutrals you are against. Spawn for resist and against creatures with low health, lords against large creatures (though as a rule, lords aren't used very often). And you should move with cockroaches so they provide the necessary units for each individual battle with neutrals...