Some cards are really powerful:
Rhystic Study for example. Does your deck always have those staples or do you try to find cards that do the same thing but fit your theme, have in-built synergies or some other factors that make the cards really cool? This question is in the context of "you've already included all the necessary cards for that archetype (=your blink deck already has
Mulldrifter) but you still have a few card slots left" - how do you fill those slots? Does
Rhystic Study go in or is there a situation where you would pick something else and why?
EDIT: I like to add all the good flavourful cards first, then look for a few obscure, sub-optimal ones and fill the rest in with staples. Staples are staples for a reason: they always do their job effectively and usually add a layer of consistency to my decks. Hence I feel like it's
a good thing to add them for the sake of consistent game play.