Sorry for the off-topic, but what's wrong with the lottery? First come, first served! ;) The explosion and chain lightning spells provide a huge number of additional tactical options, so you always need to think about whether your opponent might have them and find ways to counter them.

The thing is, there might be only one "item" on the map, and it could be much closer to one of the opponents. As for countermeasures, there's resistance, which affects everyone differently, but I find its extreme unpredictability very annoying. You spend ages exploring, pulling out elementals and angels from snow and swamps, and then suddenly, you get one item (which is easier to defend if it's nearby), and that's it :(

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In general, I would suggest limiting the explosion spell (and, in principle, all 5th-level spells) to require a certain amount of wisdom experience and a built 5th-level guild, with no books or items available without that. I think this would balance the element of randomness a bit.

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If you use your logic, then it's unclear why heroes are given troops at the start, a spell in the spellbook, etc. They can break through to a neighbor and fight him.

I suspect that Heroes is designed for games of varying lengths - both long and short. And tournament practice confirms this.

The logic is: if you have a hammer, why would you use it to hit your neighbor on the head? :D