So, obviously, as with anything there are good things within the overall bad product. I'll go gradually.
The unexpected success stories
To me personally, the biggest one is sunsfan and jenkins. Watching them on the NA DPC was pretty painful. But now that it's toned down on the major cast, their chemistry, banter and conversation is absolutely amazing. Whenever they're commentating a game, I'll be watching for sure.
Ephey. This is the first time I've seen this person working dota events, and she is quite insightful. She has very interesting thoughts about drafts, and explains them clearly. And for a newbie panelist, she has decent chemistry with the established talent.
The solid cornerstones
Some of the talent is just consistent high quality content, and are great at what they do. I'm talking about Lacoste, Lizzard, ODpixel, fogged, AUI, Cap, tsunami, Synderen, BSJ, Kyle, Teaguvnor. They all have a specific niche on the panel/cast and they all do what they do very well.
I believe the weakness of the panels, and what's caused them to be hard to watch at times is the low quality hosts. Maybe I'm just biased because after watching the NBA on TNT, and someone like Ernie Johnson do what they do, coming to this and watching this was like stepping into the dumpster.
Sheever. Constantly interrupts panelists, sometimes quite literally while they're explaining their thoughts about a pick. Often times just to say what they were about to say, explain in a worse way. Still stumbles in her sentences. Very rarely (if ever) actually contributes to the conversation. I think the breaking point for me was during the TNC/VG post game 1 panel, while people were trying to talk about the game, she decided to just call time of death on TNC's run in the tournament. It was really weird to hear her go on for about 5 full minutes how SEA were in deep trouble and TNC aren't looking good (after they went toe to toe with the previous major finalist) during a series. between games 1 and 2 of the series.
Rich. I don't know why this dude is hosting dota events. No charisma, not funny, doesn't know much about dota. I don't wanna say much more about rich because i genuinely don't understand why he's hosting a major over the people who were actually hosting DPC leagues, like dakota and tsunami.
Other weak points
Gareth. Dude cannot cast. Always sounds unbelievably shocked about everything in game. Can't pronounce words. Can't finish a train of thought. Baffles me that he's at the major over Moxi and Bkop.
I have no real problem with slacks I just don't know why he's on the panel. He can't (and shouldn't) restrain himself from being himself, but who he is isn't made for a panel. He's an excellent "other stuff" guy (interviews, content, skits) because he's actually really funny.
Tl;dr: the two hosts are extremely lackluster and actively greatly deteriorate the quality of the content. I know you guys are sheever/Rich stans, and will probably not like this post, but I hope a janitor at valve is reading this for a actual unbiased feedback.