Apart from the fact that Healy (1/10) seems universally disliked (and rightly so IMO) there's a fair variance of opinion when it comes to the Ch9 guys.
I used to rate Tony Grieg (5/10) but he's become really sour and pissed off for some reason recently, and I don't enjoy him as much as I used to. I've always thought Lawry (4/10) was a dud, but like a few people here I think he's improved recently. Maybe the three-man commentary booth has helped him.
I still think Tubs (2/10) is terrible. And while he was a bit refreshed by Slats' (7/10) entrance to the booth initially, in that they could reminisce a fair bit about not-so-long-ago playing days, it's become just about a caricature by now, and it's not that funny anyway. The worst is when he starts that drunk-guy-at-the-pub HAAAHAAAHAAA laugh at the slightest cheeky/blokey remark, particularly when they mike up players during the Twenty20's. Personally I don't think he offers much.
BTW, Slater's "are you ready to rock'n'roll?!?!" before Rogue Traders' act on Friday was hysterically bad. Not his fault but I laughed out loud. He's probably being groomed long term for a Nicholas role, and I reckon he could fill that admirably. Slater is generally good and generally I think his worst moments are when he's being brought down by the other guys.
I don't mind Nicholas (6/10), although it is easy to see what annoys him about other people. I kinda like him as the main MC of the commentary booth though, and I feel that being the first openly homosexual commentator, he was guaranteed to get a fair bit of stick, whether he deserved it or not.
Richie (6/10) used to be gold, but I've felt he's been past it for a while now, and it seems to me he's occasionally inexplicably confused, and age had to catch up with him sooner or later. He's always had a tendency to repetition, but as has been noted by other posters (not that you could miss it), he's definitely gotten way worse in this regard, again, to the point of caricature.
Ian Chappell (6/10) is a really mixed bag - it is true that he comes up with insights that aren't self-evident, and I actually like him quite a bit as a guy. But his obsession with providing a narrative for a game and ramming the point home constantly is really tiresome, as well as some of his more familiar tropes (To beat Australia, you must be as aggressive, bashing players for hours on end for not turning a comfortable run and a bit into a second run, etc, etc). His sense of humor is really hit and miss, too.