Bahrain should try running the more open
Outer Circuit layout, as suggested by F1Fanatic after this years boring race. The guy who came up with the idea of using the new Grand Prix layout with the twisty section in the middle obviously has zero understanding of what makes Formula One cars pass each other.
The Albert Park circuit in Melbourne is pretty good, although opening up turn 6 a bit could provide better overtaking opportunities in turn 9. Getting rid of turn 15 completely would also make it much easier to get a good draft down to turn 1.
Sepang in Malaysia is good as well. Removing turn 2 could possibly make overtaking into turn 1 a lot easier, since the car being passed won't have the inside line advantage immediately after turn 1. Turn 13 and 14, although being technically difficult, could be made to be more of a regular single hairpin to make overtaking easier. Turn 15 is awesome and we need more of those in Formula One.
Shanghai International Circuit in China: It's very hard to pass into turn 1 here because of turn 2 and 3, but I think those turns give the track some character. Other than that, this track is actually pretty good, although the Grand Prix itself needs a lot more spectators, if you ask Bernie.
Circuit de Catalunya in Spain: I don't even know where to begin. First of all the new chicane in the last sector is completely and utterly stupid. In fact, most chicanes are. Turn 1 and 2 serve as a chicane as well and, while being exciting to watch because of the speed and the elevation changes, only hinders overtaking into turn 1. Then there's a huge infield section with short straights, and lame corners which may be technically challenging but doesn't really provide any overtaking. Turn 10, La Caixa, is the only real overtaking spot in the infield section, and that's too bad for a track with excellent location and excellent elevation changes.
Monaco is somewhat sacred. The chicane after the tunnel is actually okay, because it doesn't give the inside line advantage to any car during a pass. Turns 13-14 and 15-16 need to go though. This would make it easier pass under braking to Rascasse. If you're worried about speed, maybe you can tighten Tabac a little.
Turkey is awesome. 'Nuff said. Well maybe you could get rid of the irrelevant turn 4 to open up the run down to turn 7. Turn 8 is

and turn 9 is good. Turn 12-13-14 could do with losing turn 13 to make passing easier, although it's not that big a problem. Vettel almost overtook someone here this year.
Circuit Gilles-Villeneuve in Canada is a fantastic track. I would like to see turn 1 opened up or removed completely to make passing into turn 2 a lot easier. Remove the chicane after turn two and increase the distance between turn 6 and 7 and you have yourself a decent overtaking spot at turn 6. Turn 10 is great.
Valencia: a lot of people hate it. From a driver's point of view though, it has a terrific flow. It does have a lot of pointless twists and turns and chicanes though. Firstly, getting rid of turn 2 and 3 and then increasing the distance significantly between turn 4 and 5 would help. The chicane-like turn 12-13 has to be revised so that passing is improved going into turn 12. The fast and twisty last sector makes it hard to pass into the last hairpin, especially because braking for the hairpin is already tricky because of the unsettled car you have coming out of turn 24.
Silverstone: What an idiot to get rid of Bridge and replace it with that rubbish infield section. I suppose the new section does create an overtaking spot at Brooklands, but the rest of the section is pointless. Also, don't use the chicane at Vale. Silverstone does have its problems with overtaking because it's very hard to get close to another car going through all of the fast, downforce-demanding corners.
Hockenheim I don't really have any experience with. Alonso was able to overtake here though, which is more than can be said of Abu Dhabi.
The Hungaroring is one more of those tracks with a lot of pointless tracks. I don't see any overtaking spots other than turn 1 here, and perhaps you should just demolish the track and design a completely new one.
Spa is a fantastic track. The new chicane is actually not that bad, because the distance between the corners is quite big compared to other chicanes on the calendar. La Source would still be more exciting without the chicane though.
Monza: Get rid of that god-damned Variante del Rettifilo. Increase the distance between turn 4 and 5 in the Variante della Roggia or get rid of that one completely as well. Variante Ascari is incredibly exciting due to the technicality and pure speed, but I have a feeling that getting rid of it and just having a fast left-hander here would probably make it easier to pass under braking to Parabolica.
Singapore: Turn 1-2-3 needs to be revised somehow. I don't know how, but it should be a lot easier to pass into turn 1 than it is right now. Turn 7 is actually decent and I believe we've seen a few moves here. Get rid of the --- chicane. Who the hell thought it would be a good idea to place a very narrow chicane here, giving the drivers only one racing line through it? Turn 16, 17, 18, 19, 20 and 21 are all just "meh" to me. I don't see the point of them.
Suzuka is excellent. The chicane in the last corner works because the distance between the two corners is short enough to award risky overtaking moves here. If you outbrake your opponent and intentionally overshoot the first part of the chicane, you should be able to get away with a pass. The esses make following another car pretty hard, but I don't want to change such an integral part of the track. I believe Kobayashi demonstrated at turn 11 why hairpins are good for Formula One this year.
Korea: Let me just say that anything between turn 4 and turn 17 needs to go. Do it over. This track is doomed if you don't.
Interlagos has a fantastic flow. I don't really want to mess with it that much, although some parts of the infield section are a bit ---.
Abu Dhabi has some problems, we all know that. Martin Whitmarsh pointed to the chicane (turn 8 and 9) after the backstraight, and I think he's right. Either get rid of the chicane completely and allow a huuuuge run down to turn 11, or revise the corners to facilitate overtaking. Revise turn 11-12-13 - it should just be a single, semi-tight corner. Opening up turn 19 a bit and getting rid of turn 20 could make passing into turn 21 a lot easier. Also, get rid of the absolutely stupid turn 5-6 chicane - what is the purpose of a chicane when you have a tight hairpin coming up immediately after it?
The new Jaypee Group Circuit in India actually looks very promising. It has a few of Tilke's trademark chicanes and pointless corners, but the first sector as well as the last sector both look very good.
One thing that I think holds for all tracks is that we need less tarmac run-offs. Yes the drivers risk more, but I don't really think Fernando Alonso missing the exit 5 or 6 times in Abu Dhabi was very exciting. To be frank, I'd rather he smashed into a wall for those antics. Then we wouldn't have to see him waving at Petrov like an idiot either.
That's the Formula One calendar in my opinion, but I'd like to hear if you agree or disagree.