Pros:

-Map flows well enough.
-Some really nice set pieces if you take the map slowly and look.
-Bots were intelligent enough.
-1st map was visually pleasing.

Cons:

-Same old scenery you'll find in a lot of other maps.  (Mall, church, cemetary, CEDA center, train tracks, airport)
-Comic effects seemed rather tacked on.  I only noticed them in the first and last maps and even then they didn't leave much of an impression.

Conclusion:

The campaign as a whole felt like a compilation of various other stock maps.  The different settings flowed surprisingly well together but I play custom maps with the intent to experience new scenery, not a summary of what I've already seen.  The only things that were new and interesting were the hidden set pieces for those who would actually look for them.

Pros:

MASSIVE environments for each map.
Each map had several memorable scenes.

Cons:

Unintuitive pathing, almost silly-bad at times.  Even worse, this is tends to happen during the constant horde events.

Conclusion:

Was a little confused as to why anyone would think to blow up the well, let alone hide in it but that aside, it was one of the most visually pleasing maps I've played.

Pros:

-Mirror's Edge styled environment.
-Mostly good bot ai.

Cons:

-AI fails when it comes to jumping the gap on one of the earlier maps.
-No finale/abrupt ending.

Conclusion:

Just like the game this campaign was seemingly based off of, it was short, but sweet.

The environment, though drastically different from every other campaign available, could of been a bit more varied.  Didn't care much for climbing up 3-4 floors of the same building's loop or for the number of unlit hallways, but the map does transition from area to area well enough.

Pros:

-Surprisingly varied prison setting
-The entire boat level was amazing
-Multiple paths
-The last map's view.
-Good bot ai
-Custom melee weapon
-Custom music

Cons:

-Water's reflection of skybox glitched for me
-Bodies disappear in map 3
-It's a port

Conclusion:

The cons are just little nitpicks which you forget about while you're taking in the otherwise flawless campaign.

Pros:

-2nd map was fun:  hallway of witches and its cola event which made you push forward.
-Unique/challenging finale.  Tip:  throw the gas cans up so you don't have to run back down.

Cons:

-1st and 3rd maps were just bland/boring.  Their cola events were equally boring since you were just backtracking through the same environments.
-3rd map had a 2nd cola event wherein you back track down a long elevator ride, get the cola, go back up another long ride, and then it turns out that you didn't even need the cola.  Why the pointless backtracking?

Conclusion:

I was vaguely aware of a sky theme going on, but it seemed more like a map which just had an empty background in the form of a blank sky.  So visually, eh.  It's hard to justify playing this campaign when half of it is just so bad.

At some point in the 3rd map, there was a skytrain.  But it wasn't so much a skytrain as it was a typical hulking diesel engine which happened to float.  I thought it was the funniest thing.

Pros:

-Good atmosphere.
-Ventilation shaft area was really trippy in particular.
-That tank placement.
-Challenging boss fight.
-Innovative sandbox sort of gameplay.
-Randomized glyph location and slightly different enviornments per play.

Cons:

-Terrible, terrible bot navigation.  
-Reaching one of the glyphs was a little unintuitive, needing to shoot open a locked door.
-A tad short.
-Slight lag in some areas.

Conclusion:

Unlike most other campaigns that rush you from spawn to saferoom, spawn to saferoom, and etc, this offers a more sandbox experience encouraging players to explore the map in its entirety.  It's a bit of a struggle though when bots don't follow you, get stuck on objects, or refuse to pick up health kits, and they're just deadweight during the bossfight.

Pros:

-Nostalgic music and scenery (especially for the first map)
-(Bill) Crates*
-Custom enemies*
-Custom graffiti*
-Raft*

Cons:

-Unnecessary "platforming" elements.
-Crates, sometimes unbreakable unless shot, occasionally contain gas and thus EXPLODE in your face when you're hoping for supplies.
-All of the enemies, aside from typical lfd infected, just sit there, posing no threat at all.
-Graffiti's attempt at humor is just juvenile/bad.
-Raft was useless, better off trudging through the water, moving at my own pace.

Conclusion:

The levels were full of details that made me remember crash bandicoot, as well as some other videogames which the map referenced, however a lot of these details did nothing to gameplay and at times made the game worse.  Why bother with platforming elements if you can just walk around?  Why have custom enemies if they're just going to be static?  The end boss wasn't even threatening so much as it was a "shoot at me when you're not too busy with the horde, I'll just sit here, spinning."

Really, the only thing the campaign has going for it is the nostalgia factor.  Aside from that... :/

Pros:

Chinese healthpacks/saferooms.
Opening the door during the horde event in chapter 2 was different-though nothing all that amazing.

Cons:

Ridiculously short.
The subway car moving by itself was silly.
Finale was anti climactic and cramped.

Conclusion:

The last two maps did not seem China ish at all.  All in all, it was a very lackluster campaign with the occasional Chinese symbols on signs.

Pros:

-Great opening
-Different routes to progress through, so the gameplay isn't as static on a second play through.
-Visually distinct and varied settings.
-Sink holes
-A lot of unique graffiti, mostly in spanish.
-Custom skins for common infected.
-CEDA
-Easter eggs.

Cons:

Some occasionally glitchy tanks and witches.

Conclusion:

Can't stress how visually detailed this map was.

Just to nitpick though, the tank spawned and got stuck behind the alarm rigged door.  He just kinda died when we opened the door too.  Also, there was a witch stuck in the ground, just before the subway station.  She wouldn't respond to anything, like being shot.

Pros:

Detailed visuals
Getting the boat and its following horde event
Nice transitions
End tanks
Custom melee weapon was rather comical.
Original voice acting.
Cleverest easter egg ever put into a map.

Cons:

-Prison layout was a bit confusing.
-AI refuses to get on train when it leaves.

Very minor, really.

Conclusion:

Visually great, varied settings, nice events, custom skins for infected and weapons.
Despite the ai not hopping onto the train as intended, the train is basically a safehouse so death isn't too much of a concern.  Though a friend of mine was idle so he lost his preferred gear.

Pros:

-Unique minimal sort of atmosphere, familiar to yet different from Portal.  Arguably more oppressive than Portal's with the lack of anyone commenting on your progress.
-Fuel used for choice of upgrades.
-The hinting of traps before actually seeing them.
-The traps' solutions/route being randomly generated.
-The hanging car trap in particular.
-The finale throwing every trap you learned of in quick succession.
-Great ending.

Cons:

-Some rather deadly glitches.
-Unfairly difficult at times.
-Laser room's end was a bit unforgiving.
-Bot navigation is a nightmare.  Won't pick up spare health packs.  Dealing with traps is another headache.

Conclusion:

Unique game play elements, visually great, however it suffered from some really painful glitches:

-In the room with the cars overhead, my one friend somehow fell to his death mid cut scene without moving.  
-In the room with the garbage bin and the tanks, the garbage bin defied all laws of physics and rapidly shot in every which direction killing all of us.  Though, that may of been the source engine's fault more so than the author's.

Pros:

Unique lighting while outside.
The last map in the campaign was visually unique.
The special effects for when you activate the finale.
THAT ENDING.

Cons:

As unique as the lighting was, it was an awful lot of brown.
Bunker areas were occasionally bland.
Couldn't quite see during the finale due to special effects.

Conclusion:

The entire time I was wondering "why are we pressing forward into this CLEARLY DANGEROUS underground military bunker if we want to reach safety?"

And then the ending hit.  And it all made sense.