I don't mind the 9 guys, but probably because Richie, Tony, Bill and Chappell have been at it for so long that I've rarely ever watched cricket on telly without them commentating - just used to it I suppose.
Lawry is one-eyed about Australia, and doesn't bother trying to maintain composure. Most of the time you laugh at it because he comes across as a bit of a goose, but nothing complements a big wicket like Bill's "Got Him, YES, Gone" action. (BTW brilliantly taken off, again, in the most recent 12th Man - "Got him, gone" "actually bill, that's nowhere near out". "Well, I thought it looked plumb". "The Australians not even bothering to appeal there actually Bill").
Healy is not a good commentator, apart from when he's talking about wicket-keeping technicalities. Taylor is pretty much a non-entity...
I think Chappelli's actually been much better this year than in recent times - less whining about the captain not doing their job right in his opinion.
Slats is good and so is Nicholas.
A few people have mentioned that they seem to try and hype the action to make it sound more gripping than it is, or that they dumb down the game. My reaction to that would be: "Well, duh!" Their job is not to provide brilliant insightful commentary. It is to get people to keep on watching the program. Now, good commentary is one significant aspect of that job, but it also involves papering over the cracks in otherwise dull or one-sided affairs were people might be tempted to change to the tennis or whatever by keeping the tempo up and the (apparent) excitement coming.
Finally, its a question of target audiences. 9 obviously wants to get in a bigger crowd than just the cricket tragics out there - we're all going to watch anyway - and the tendency towards appealling to "not serious" cricket fans is much more pronounced in the commentary on the ODIs than in the Tests, reflecting the different audiences of the two games. They also want to get in the people who will tune in because they enjoy watching the Poms, Saffies, Kiwis, whoever, being ground into the dirt and want to revel in it, and the people who don't know much about cricket at all, but will watch anything with some colour and movement. The commentary needs to appeal to all these target audiences, so its not surprising that the demographic on this website doesn't enjoy everything they do.