Very disappointing meta if you ask me...
I think most players have hit the nail pretty much on the head and diversity in the format boils down to two problem children.
I think the restricting of Mentor opened things up a bit and I approve of the thorn restriction, I think they got it right over sphere in terms of its effect on shops decks. But without the above mentioned problem children being restricted, then a lot of decks that might not otherwise have a shot, are simply relegated to inferior status.
I think we all can see the benefits with the restriction of workshop, but there are so additional benefits to Mental Misstep being restricted, such as Dredge gets weakened, they no longer get a free counter "Grafdigger's Cage". Heck they are either main decking and/or side boarding a full compliment of them, and it quite honestly brings back dark ritual which I think is a good thing for the format.
Perhaps i'm just living in the past, thinking back to the days where the metagame had a large contingent of viable decks all at once. Keeper / Dragon / Mask / TnT / Stax / Blue Control / Hulk / Gro / Fish / Mono-Black and a plethora of variants that flirted with the tier 1 mark.