I usually describe Dominion as “The first Deck Builder ever made, and also the worst.” The customers will usually chuckle, and I’ll explain that “worst” doesn’t mean “bad”, but the “worst” part is because it was the first, and (almost) every deck builder that comes afterwards improves on the formula in some really interesting ways.
Co-op (Harry Potter Battle for Hogwarts, Aeon’s End, etc…), Race (Clank!, El Dorado, etc…), tableau (Empires of the North, Seasons), faster (Star Realms, Hero Realms), bigger (Arctic Scavengers, Clank! Legacy), area control wargame (Tyrants of the Underdark), deck that never grows (Mystic Vale)… all of them take what Dominion does and improves on it in really interesting ways.
Which isn’t to say everyone will like all of them, but it is to say that almost every Deck Builder kinda scratches the same itch, and it’s hard for me to recommend the simplest one unless you have played very few games and any complexity whatsoever scares you.
All that stated, I have played SR:C a long time ago, and I remember having a good time with it but some of the mechanics were a little fiddly. I think they ironed them out for the Dragonfire game they made with the same rules, but again, I only played it once years ago. I remember having fun, though, so it’s probably a safe recommendation, especially if the theme/setting appeals to you!