ok I made a bad example with Sundial ( I thought so, to be honest)
but your example of sundial doesn't apply to most decks and most players as well. As you have said, normal strategies do not favour drawing the same card all the time.
AS long as the average game play is considered, slightly adjusting the deck randomization won't hurt.
I'm not suggesting a big change here, maybe just a small change, like if 6 cards of same nature (e.g. all creatures) are stacked together, insert one non-creature card between those 6, giving you an opportunity to get other cards other than dead creature cards