I will admit that the reason I was drawn into Dominion initially was because of its symmetry. I knew about MTG and in my head it was a sinking hole for money where the player with the best deck and the most money would always win. So Dominion was a fresh experience because it allowed equal access to everything.
I second that.
From playing some games with Dark Ages, though, Shelters do not deviate from the symmetry promise. Everyone still starts with the identical deck. I really enjoy playing with them. Ruins even aren't so asymmetric because they are all so bad. Some are just a little worse than others. Knights, on the other hand, I don't like very much (even though they all attack, they are a close third behind Black Market and Tournament as the worst offenders of equal access). Haven't played more than a few games with them, though.
The whole point of
Dominion games is asymmetry: you usually don't have unlimited VP available (Monument, Goons + Ambassador and Bishop + a few DA cards aside), so the player who gets the most, wins. If you piledrive, say, Cities or Laboratories, you are the only player who has access to them and then you have quite an advantage there. If it wasn't for asymmetry, every
Dominion game would end on a draw. Now, I can see why Black Market isn't everyone's favorite card, because getting the only Mountebank in the whole game can be devastating and is completely luck-dependent, and the same is true for Tournament to a lesser extent (because it depends on luck significantly less), but getting to $5 is a matter of luck only when at least one player opens 5/2 and another player does not. Sure, the player going first always has additional advantage from Knights being on the table, but that's also true for attack cards. While Knights aren't bad cards, they are worse than the power 5 cards, and usually getting a specific Knight is more a matter of choice.
In Dominion, every player has equal chances of winning the game before the first player is decided and Knights, Tournament and Black Market do not change that.