I think casual is where it gets less fun because if one casual player in a pool of several casual players pulls better cards than everyone else, especially at common and uncommon, pulling a Comet Storm in your rare slot in a pack of Modern Masters 2015 is that much worse.
I don't think Wizards is just going to sit by and let this happen though. My huge hope is that with standard going to two, two set blocks coming soon with Origins, this is going to make WotC R&D tighten up sets and have less chaff.
I think if they really wanted to balance better for casual, they should stick better cards in preconstructed decks.
It'd also help with the problem where even slightly less casual play like FNM events get less painful in the wallet with great cards being near giveaways. It'd be great for game shops on the second hand market too. I'm guessing that enough people would more willing to spend at 15 bucks per card than at 30 or 40. The price on Thoughtseize completely sucks at 20 bucks, and prior to the reprint in Theros it was *60*.