Late to the party here.
While I'm generally enjoying the game, and not too upset at the storyline (I can see where Battuta is coming from, but I don't find it nearly as bad as he puts it), I must say I am really disappointed with the few Protoss missions they tossed into the mix. I'm playing on Hard, and while the majority of Terran missions have achievements and objectives that can be met with a little creativity, these Protoss ones (especially the last 3) are crap. Now, granted, I'm achievement-whoring here but honestly.
Mission 2: While the fight against fellow Protoss is fine and dandy, I was more than a little miffed that I had to confront an ever-more-powerful uber boss too. Honestly? Oh, and I have to do this is 25 minutes or less? I managed to speed run it with Dark Templar for the timed achievement but none of the others, then replayed and walked over the map with templar, immortals, and stalkers for the other two. The mission design just felt like it required two playthroughs - which is unfortunate, because I never had to do that with the Terran missions. Speed run achievements just frustrate me in general though - it rewards for micromanagement abilities, not strategy play. That's one of my biggest beefs with Blizzard RTS games in general though - the strategy element is often ignored in favor of micromanaging unit abilities.
Mission 3: At first I thought "Oh, this is more like it, finally a mission where I can pound the snot out of the Zerg with my superior firepower. Wait... what? Another timed achievement? Oh, and waves of increasingly painful Zerg sneak attacks through Nydus worms. All without aerial units or, indeed, anything capable of killing them other than Stalkers, which have left me really underwhelmed compared to their Dragoon precursors. Wonderful! Alright fine... I exploit Blink to its full potential and finish the mission in 6 minutes. HA! But naturally, that doesn't get me all the objectives... so then I go back, power both towers, and cap the final tentacle just as my final structure in my virtually undefended base falls to the Zerg (after reloading 4 times so Zeratul will Blink properly). Objectives done, achievements done, but it doesn't feel satisfying in the slightest. Can't someone give me a mission where I can take a good old Protoss base and wipe out a superior force after an epic fight to the death with mixed units to counter any threat? I miss those! You could give it an achievement called "Kick the Snot Out of the Hydralisk's Teeth" for cleaning the map (Hey, you gave me Feats of Strength achievements for doing it on earlier missions). Maybe the final Prophecy mission will do it...
Mission 4: Hey, this doesn't look so bad. I guess I can just build up and... oh you're kidding, a defend for X minutes mission? Kiss my ass Blizzard. This is worse than timed offensive missions - now I have to micromanage unit abilities. Oh great, and you're going to throw ultra-powerful boss units at me on top of the regular Zerg fodder for my photon cannons. Blizzard, I think you missed the point somewhere: Zerg is supposed to run attack waves with large numbers of cheap, mixed units to overwhelm the enemy - adding an overpowered extra unit to the mix ruins the point - I might as well be fighting Protoss that cheat to produce units at speed. So instead of building proper strategic counters in units to a unit fight, I get to sit a micromanage Graviton Beams for twenty ****ing minutes while trying to run a simultaneous defense. This is tomorrow's project... seeing they send very few detectors, I think I'm going to plunk a wall of dark templar on the bridges and let my Collosi kick some ass for a while. Maybe then I'll get the bonus objective and rack up the necessary addition kills.
The Terran mission design has been great thus far, but these Protoss missions are CRAP. Protoss is my favorite race by far, and I'm now to the point where I just want these Prophecy missions over and done with as expediently as possible because the missions are so bloody unrewarding - it just feels like painful, monotonous grind, propelled entirely by scripted events and never allowing the player to actually match wits and abilities against a dynamic foe - and no, I don't want to resort to Custom games to get that feeling. All I can say is the Protoss expansion to SC2 had better be a damn sight better than these. I can safely say that, once completed with all the remaining achievements in the fourth mission, I will never play these ****ty missions again. It almost makes me want to use that laser drill again... almost.