Player vs. Player Combat. Yes/No?
Yes. It seems very balanced (just engaging in it for the sake of it isn't a good idea, especially the way blocks are balanced to be easier to obtain than attacks).
A specific scenario which has some additional constraints or even a different scoring?
Meh. A lot of the scenarios seem like they are less in the spirit of Fischer random and 70 factorial factorial Dominion kingdoms and more in the spirit of, I'm a boardgame sampler collector, I've already played this 80$ board game twice, it's about time I bought a new game, well maybe i'll use one of these variant rules and I can pretend this is a different game.
Few of them seem like they would improve the game, or even change things up without damaging the game in an equal and opposite fashion. The ones geared towards shortening the game will reduce strategy. I don't remember any of the variants having equal or greater length, except maybe rampage/upping city levels. Those I'm in favor of, if only because in Mage Knights I we flattened the game long before the allotted time, and that was
in spite of absurdly dry mana in the early rounds. I'm inclined to take the arrogant interpretation of those results and say that all us ex Dominion players are really good at deckbuilding games.
Include the expansion "Lost Legions". Yes/No?
I expect it would have a strictly positive effect on my experience, but I'm not dying to have it as soon as possible. I'd rather you not get burned out on modding due to additional difficulties, so we can stick with the base game.
Auctioning the Heroes where you have to pay fame to get a certain hero. Yes/No ?
Why not? At the worst, we all bid 0 and nothing happens. I would probably bid 0, except maybe on the rampage variant, where I might bid, like, one.
I was pretty surprised that the rules suggested bidding begin-of-game fame. That is sooo expensive, because it delays level 2 by 1 fame, which not only delays level 3 by 1 fame, but delays it even more because you were in a weaker state for a longer period of time, and et cetera and et cetera.
I'm also surprised that the creator has what seems to me to be an inconsistent position on player information regarding initial conditions. He wants the variant to be chosen -before- heroes are auctioned; that's the way I would have it too. But the other initial conditions (I suppose because they are the random ones, but I don't see that as being a basis), like starting source mana, initial offers, etc, are supposed to be produced only after hero auction. Why come? It's like being required to commit to which 3/4 opening you want before the 5's are revealed. To me.
Random Tiles Orientation for more flexible maps. Yes/No?
Why not?
Changing the difficulty level by change the level of the cities or Megapolis (multiple cities on one spot). Yes/No?
Megapolis seems kinda swingy, I'm undecided on it. Higher level cities or some other difficulty increaser seems necessary because MK1 blazed pretty fast.
Friendly Mana: You're not allowed to take Gold Mana Dice if the specific color dice is available in the source. Yes/No?
Unfriendly mana is already fueling day 5 wins, so no.
Making it harder by starting at Night. Yes/No?
This seems like inferior design. The flow of buying spells day 1 to use night 1 seems best to me.
Start at Day but at the end of the Round, roll two mana dice. If any of them is black, night falls and it is Night until the end of the game. Yes/No?
No.
"Rampage" variant for more rampaging enemies. Yes/No?
This could be cool. One thing I like is that it gives you a little bit more renewable fame source-age. In teams the need for that gets mitigated quite a bit by keeps and PVP though, so if we do in fact do teams I'd rather go without. In free for all, assaulting a keep doesn't seem very attractive, you only get half the fame, for the same accomplishment and you're not sure the player you're damaging is the one who will beat you out for first place.
Interactive Combat where an opponent "controls" the attacked enemies. Yes/No?
No. Not a fan of rock paper scissors. Even less of a fan of being on a forum and having the ability to card count and calculate a Nash equilibrium for the possible decisions, which the perfectionist in me would compel me to do.
"More Deckbuilding": Action Upgrades/Drafting/No ?
The choice aspect seems promising, but the only proposed way of doing it accelerates the game, and I think we need deceleration.
I think the offer gives you choice enough. I'm really disappointed and almost surprised that there is no incentivizer for picking neglected Advanced Actions from the offer. Terra Mystica and Small World both have one. "Fame tokens" would work rather easily as an incentive for taking previously unwanted Advanced Actions, and as slightly offseting the effect of a player getting a powerful AA before any of the other players even got a chance to take it.