But wouldn't you argue that fits the context since Reach is about defending a planet from Invasion?
My issue with the Reach campaign is that it never really stretched it's legs into the full sandbox. You never got those kind of epic, multi-faceted missions that took you from indoor environments to outdoor environments, and offered those epic battles that mixed infantry combat and vehicular combat. The closest we really ever got was the second Swordbase mission (though flying through the city was also cool).
As far as the voice-acting, I didn't really think it was any worse than any other Halo. Which characters/moments stood out to you as particularly bad?
I enjoyed the Reach campaign, but for me the main issue was/is the frame-rate drops during high enemy encounters; it kind of ruined the DMR gunplay/pace-shots that Bungie were going for (which imo was fine for campaign, less so in mp).
I thought Halo 3 & ODST were much better in that regard.
Edit: Just to remain on topic, Halo 4 is awful compared to H3 (which was awesome and the reason for my 360 purchase). Their 60fps claims for H5 is a dubious proposition and I wouldn't be surprised if the MS/343i "think-tank" meeting for H5 went like so:
Bean counter A: "Why did Halo 4 drop off? I mean we did our best CoD box-ticking exercise attempt?"
Bean counter B: "I know!!! CoD is 60fps!!!
343i dev: "Errr yeah...well maybe 45-60fps...mutter...fucking assholes..."
Bean counter A: "Bingo! Announce 60fps asap!"
Bean counter B: "TV, TV, TV"
Bean counter A: "Fuck me!! You're right son! Announce a TV Show first. Take a percentage of H5's budget, give it to Spielberg so we can name drop him too! Man...Sony got nothing on me!"
Bean counter B: "Announce 60fps at E3 for dat double whammy, we don't need any gameplay footage either."
343i dev: "...I dreamed a dream in time gone by....when hope was high...and life worth living..."