I think a practical suit is cooler than one that's made to look cool. It's just a video game, but I often overthink EVERYTHING.

it's been said that the only flaw in the armor is the weak spinal protection. break that and the body won't sync well with the suit. leading to spasms in armor movement that pulverise the body inside.

in terms of price tag however
being as just one man with this suit was able to do what he did makes it seem more like a good investment in the name of humanity's self preservation.

Also of note, Halo is fiction (duh). Where the soldier gets hit doesn't matter (at least in the games). In real life, getting shot in the joints would be far worse than getting shot in, say, the chest, which has thick plating over it. A sniper could potentially one-shot the wearer in the neck, after the suit's shield is depleted.

the one shot kill in the neck works in the game too.
but if their is one thing i grip about in this halo universe assuming parts of it could be made real, it would be the OP pistol

Oh, it does? I've only played the game at a friend's house, so I don't know way too much about it. But anyway, yeah. An expert sniper could still down you. Why not put some overlaying plates over the joints, like an armadillo's back? I would think the extra weight and movement restriction probably wouldn't be that severe, considering their level of technological advancement.

shield development seems to be the higher priority in their budget, that and making the spartan armor cheap enough to mass produce can result in design flaws.

personally in the game before i quit console gaming (halo 5 got me off xbox and i got bored of ps4) flood was my main favorite game. there's a game mode i can't remember for halo5 but you started off with a sniper and shotgun and went at each other. that game mode was epic.

I'm not much into FPSs, but I gotta say, Halo does look pretty cool.