Well, Dominion is designed in a way that makes it balanced with standard rules. Changing the rules randomly would inevitably lead to somecards being either crazy strong or very weak. Examples:
• This game: the game ends when the duchies and only one other supply pile are depleted (This is an additional game ending condition to those already existing).
- as already pointed out, cursers get even stronger. Also Count and Duke become very powerful.
• This game: all treasure cards cost one coin extra.
- makes Upgrade and Remake much more swingy: you now Upgrade Coppers into $2s, which is great if there are spammable $2s, and awful if you're forced to gain Estates. Granted, Poor House has a similar problem. It may also slow the game down a lot if you cannot open Silver/Silver.
• This game: (2 player preferred) there are 12 kingdoms and each kingdom has only 8 cards.
- This doesn't change things up by much. Fairgrounds and Horn of Plenty obviously profit, but not more than with Black Market. I guess piledriving becomes a stronger tactic.
• This game: all estates are worth 2 victory points.
- Inheritance gets even cwazier. Also Followers/Baron to an extent.
• This game: all players start each turn with two buys.
- Gardens loves this.
• This game: the game only ends when all the estates and duchies are bought (this is the only game ending condition.)
- this one is weird. Is it intended that 3-pile endings are also eliminated? I think there are many ways for this to lead to stalemate games, where buying one more Estate/Duchy is the losing move.
So all in all, I think putting these in randomly will be bad more often than it is interesting. But I can see the value of first selecting a kingdom, and then maybe add one of those extra rules if you feel it's not exciting enough yet.