Well, if you consider arena a format, then we agree. Though, probably not on implementation. I think limited formats will just lead to stale metas again. Card disparity is not the only reason I dislike constructed. Actually, now is a *great* time to play constructed as a newb because many of the top decks are quite cheap.
Anyway, that tangent aside, I have a rogue deck in arena currently where I've gotten to "combo" shiv and spiteful smith. And it's been fun, nobody expects it! Or combo shiv with a loot hoarder or acolyte of pain. I will never get to use these cards in constructed regardless of the format limitation, it's just too weak.
Lost my first game with that deck versus a priest that was able to divine spirit and inner fire a lightwell before I could remove it. Then divine spirited a burly rockjaw later. Weird shit you'll never see in constructed. And, admittedly infuriating. Had to redeem myself by playing around *three* flamestrikes the next game. Every expansion that doesn't introduce more common board clears is a good expansion.