well, maybe only delve does that exclusively. annex does another significant thing, and wedding gives you that vp. but hey, you'll pretty much never buy these things when you don't want to gain that card.
ah, the power creep in dominion is so frustrating! you're forced to buy the new expansions to keep up! haha, that was a joke that i made just then. intuitively, having these around will make for 'stronger' games in general but if delve is there then that means ferry might not have been there, and ferry is a big deal. they all do push the game in a direction, regardless: delve lets you get silvers in bulk or in addition to other stuff more easily, wedding means bm or whatever happens to want golds on the board has more options to that end (although it's hard to pinpoint what parts of the game those decks benefit, since it is strong both at the present and at the end of the game) and annex looks like it'll make the endgame more consistent, or something.
-does 'breaking dominion' mean anything at all ever, and did any of these cards accomplish that goal?
-do the thematic elements of these cards make you feel weird
-where do you put these during setup? should you put them next to the cards they gain, so you can consider your options?