I think Rune tends to have very high-impact legendaries that don't necessarily synergize well and that is what results in cheaper decks.

You don't have to throw in 17 legendaries because they just don't work together - You're not going to summon Daria through Ginger because that's completely pointless. You can't use Daria and Ginger on the same turn because Daria banishes your hand. You're not going to run Oz in a Daria deck because most of your spells are already very low cost.

They are definitely changing that aspect of Rune. Unbodied Witch and Runie and Mysteria can all feasibly work together in some way; at the very least, including one in a deck doesn't make the others null afaik. I feel Daria limited the design space of Rune in a sense, since that card was like...~THE~ Runecraft card for the longest time and didn't really leave room for others.

The first legitimately competitive deck I ever made was Daria, actually - I wound up getting two from packs and the rest of the deck came together very easily after that. The feeling of getting Daria in your opening hand was always a little bit of a rush (until you drew the other two). That's why I'm fond of Deus Ex, it has a very similar playstyle.