Actually, after Halo 4 there were soo many different possibilities and interesting arcs they could have pursued. And I was freaking EXCITED. Until I heard Reed was writing it… So I wouldn’t say they are running out of ideas, but rather they either don’t know how to execute their ideas. They themselves can’t come up with ideas. Or the fact the lead writer didn’t want to continue off the previous story arcs and wanted to do his own thing, put his own mark and disregard everything before him. But ultimately failed because he also cut ties with any arcs HE himself wrote too.
I envisioned that Halo 5 was going to be more of a ODST detective-noir styled game where Chief drives the story that Locke must discover. And not show Cortana in her current state by ditching that altogether. But if they did, than save it till the end as a small cameo. And I would’ve also ditched the squad gameplay for this. What I’m about to explain might have given Chief and Locke equal stardom, I don’t know. Feel free to skip to the last two paragraphs where I answer your question. The next paragraph is just what I envisioned of H5.
But ditching the squads would show Lockes skill as a proficiant hitman/detective by unraveling clues about Chief, he’ll be working behind the scenes and between the lines unlike H5 where he’s constantly in the forefront interacting with others for no reason. Like with the SoS, in which he didn’t need to be a part of. But the writer included it just so we could have a few Sanghelios missions and more drama. I mean, why the hell did we need to find a small robot? To help lead us to a giant robot? I didn’t even know said small robot was guiding us through Sunion until my fifth playthrough, actually more like; until I started writing this. I mean, I would’ve just prepped myself and waited for the Guardian to show up than have a pelican get me there. The SoS were already planning to go to Sunion it seemed. And guardians take their grand ole’ time, by the time we get the small robot the Guardian was already waking up a few hours later… So that was two. Maybe three missions of wasted time? I’m sorry. I’m straying from the point. Just… Plot holes and discontinuities man… But on the other side of the spectrum Chief would drive the story as you play through past events with him experiencing the effects of PTSD, questioning his humanity and seeing hallucinations that are causing him to do things others may question. Perhaps instead of Cortana, HE was linked to the Domain. Or something like Mendicant Bias contacting Chief to activate the Guardians to repent for past sins and rally the Guardians to stop an incoming Flood threat putting Chief in bad light so HTT would have actually tied in? Yes! And than Locke would be played in a current timeframe experiencing the after-effects of Chiefs actions. (Ala, E3 some time ago) Ultimately leading up together for whatever purpose or freakin awesome climax and cliffhanger…
To add, I really wish Halo 5 went into the realm of discussing PTSD. As Halo 4 went into the subject of Schizophenia and dimentia. I adored Halo 4 for going in and taking risks by discussing a controversial topic. It was a gem, and it mirrored Josh Holmes personal experiences. It felt emotional and personal. I felt as if it was the first game to nail a controversial topic within its plot without it being shoehorned or needed as an overall plot device. As, it was never the main focus of the story. So people always disregarded it sadly. Games like TLoU, Watch Dogs, CoD, Mass Effect ect. Either failed in this regard or weren’t executed properly or meaningfully.
But as it stands… With Halo 5, the universe cannot really go anywhere meaningful after it now. It seems as if the writer just wanted to shoehorn as much dramatized melodramatic drama and action into this game and try to hit a climax and have a cliffhanger it never earned. People bring up in defense that Halo 5 is nothing more than an intro to Halo 6. Well… Obviously. But it never earned it. Nothing in Halo 5 will effect the next game except the very last scene of the Guardians EMP’ing everything. All the events of Halo 5, if they never happened would not effect where the universe goes. Guardians would still have shown up, Infinity would be on the run, and everyone would be on Sanghelios… Actually, no. What’s funny is; if the events of Halo 5 never happened; we’d actually would’ve probably have more time to prep against Cortana! We would have delayed those events because apparently Halsey already knew about her. We’d just rally Chief after his mission at Argent Moon and than BAM! A better Halo 5…
Oh man… Sorry for the long post but… The more I talk about this game the worse it gets for me. Discovering more and more wrongs, plot holes, and discontinuities like the Sanghelios missions and the fact Halo 5 as a whole was meaningless… Please… Someone help me… Please tell me Halo5 was just a dream? If not than I hope Chief wakes up in Halo 6 and looks at a cover of Halo 5 and says, “Yikes, that was a nightmare and a half… I need an aspirin.”
TL;DR: Read the first paragraph, than the last two. The giant chunk in the middle was just ideas on what I wanted H5 to be.