Rankings are subjective so remember people have their own favourites and will disagree no matter what, but you have it fairly accurate.
Lightweight is pretty solid to call, outside of Bendo at #1 it's a toss up. You could have Edgar as #2 on his wins alone and that he is currently #1 contender, or you could just rank the next guy in line Nate Diaz as #2 and I don't think anyone would have a major issue with it, beating Gomi, Cerrone and Jim Miller in succession is a great feat.
After that, I'd prol go with Pettis at #4 (don't like him personally, but it just seems 'right') although his record isn't as impressive as others. Joe Lauzon creeping in at #5 by virtue of him actually having a win last fight while Cerrone, Varner, Miller, Gullilard and the rest are coming off bad streaks.
If it was an 'MMA' list and not a UFC one, slot Melendez in at #2 and push the rest back a spot.
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Welter seems like an easy one, you have it right I reckon. Unless someone wants to be a dick and rank Nick Diaz highly even after losing to Condit (f-u Dod), #1 & #2 take care of themself. I wanna rank Kampmann third, because if it wasn't for judging robberies against Sanchez & Shields he'd be unbeaten since 2009 and have wins over Condit, Alves and Ellenberger on his rec too.
#4 Hendricks, although he looked fucking awful against Kos last time out. #5 Rory Mac, solely because he won't fight GSP so whats the point in even ranking him any higher while GSP is a 170er.
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No point in arguing who #1 is @185, this goes without saying.
Sonnen.
lol j/k.
#2 has to be Belcher for me, I don't really think it's close either unless Rashad dropped and got a win at the weight. Belcher is the only guy I could see troubling Anderson now.
#3 probably Weidmann, I'm sort of shocked he only got an hon mention although I don't rank him that highly either. Still hasn't got any major scalps on his resume, although Munoz was an impressive win.
#4 I agree it has to be Bisping, he probably beat Chael on the Jan Fox show, but didn't get the decision so here we are. He seems to be a jack of all trades but a master of none, which is why he doesn't stand out as a top contender most the time. He isn't dominant enough in winning, and lost to washed up Wandy not that long ago. #5 could be anyone, the division is so poor that Rich Franklin could be ranked here. Stann, Le, Palhares, Boetsch, whoever really.
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When you rank light heavy it goes -
#1 Jon Jones
#2 - #5 whoever got their ass whipped the least by Jon Jones.
#2 is Hendo obviously as you have it, he'll go back to the bottom after his inevitable pasting though.
#3 yeah it's Machida, I don't like him, find him incredibly boring to watch, but his style gives him the best shot of competing with Bones, he gave him a tiny bit of trouble in their first fight, and has had some spectacular KO's I guess.
Gustaffsson @ #4 for me, nice, rangy fighter who has some characteristics the same as Jones but isn't a carbon copy like Joe Rogan puts over he is. #5 is maybe Bonnar here, I am biased, the guy is on a roll with some exciting fights and he still has some milage in the tank. Plus he didn't go life and death with Brandon fucking Vera.
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tl;dr - didn't mean to write such a long ass post but went off on a tangent somewhere......
(come on, that Guida fight was very forgettable) but he's in or around there anyway. Like everyone says, theres a bunch of guys you could rank in there and I wouldn't have an issue with.