This is a pretty pivotal question. As much as classic enthusiasts say otherwise, I think, as you seem to suggest, that a full-on classic-style game would feel antiquated. On the other hand, Halo 5's movement was really divisive among the fanbase, ranging from an outright rejection of Sprint to a lukewarm/controversial reputation for Thrust. As they are, I think the Spartan Abilities are poorly implemented, but there are glimmers of goodness in there that I hope they retain in Infinite.
Like, you can't really deny how intrinsically good it feels to boost, run, and climb all over the place. You often see the sentiment that "sure, Halo 5's campaign sucked but the multiplayer was awesome!" I would bet that this is what people mean. Halo 5's movement
feels really good, even if the abilities have negative
indirect effects on the rest of the game. Finding a Doom 2016-style balance between the old and new isn't easy, but they can start by addressing the main criticism of all the abilities.
Sprint separates movement and combat. Most people have agreed that this goes against the nature of Halo, so they can fairly easily remove it and increase the Base Movement Speed. Easy enough. Clamber is a bit trickier; whether it's a quality-of-life convenience or map-stretching annoyance depends on who you ask. Spartan Charge and Ground Pound are nuisances that almost everyone agrees should be removed, while Hover and Slide are often so niche that they hardly affect the game (barring specific jump sequences). The majority of abilities are fairly easy to navigate, in terms of discussion, as their effects are pretty clear.
Thruster Pack, however, is a thornier topic. I think It has tangible effects on the game that are both positive
and negative. As many have pointed out, it extends maps due to it's hypermobile nature, with many jumps requiring players to use it, or wait awkwardly for it to recharge when it's down. By making jumps and sightlines alike larger, Thrust becomes a necessity rather than an option. Furthermore, it acts as a sort of get-out-of-jail-free card when a player is in trouble, as the boost goes farther
and faster than base movement--especially in the air--to the point where you can flat out run away from certain encounters.
On the other hand, Thrust genuinely opens up options that weren't there, before. Being able to change your momentum so quickly, on the ground or in the air adds new depth to the way players strafe to throw off their opponent's aim. In fact, Thruster Pack is able to save you from a Rocket Launcher fired at your feet, or even dodge a Sword lunge; it adds more potential to outplay your opponent, even in situations that would have been instant death in classic Halo. However good you were, a Rocket was a Rocket and you were as good as dead. Whether you chalk it up to the design of the weapons or the movement, older Halo's didn't let you avoid what you can in Halo 5, and I think allowing players to dodge instakill weapons is a great thing. This clip from Raycevick's (reallly good) Halo 5 review shares a similar sentiment:
Basically, I think it boils down to a few key topics. A separation of movement and combat (Sprint, Clamber), Cheesy abilities (Spartan Charge, Ground Pound), Pseudo-filler abilities (Hover, Slide) and overtuned mobility options (Thruster Pack). Hopefully, 343 can distill the sense of liberation and player-agency that Halo 5 offers into a better balanced experience where mobility is toned down. Let players dodge, juke, and run around gung-ho at a fast pace; don't bog them down with guns-down gameplay, artificially extended maps (vertically
and horizontally), and easy-bake escape options.
Anyway, didn't mean to get carried away and write an essay. Might post this on the Halo forums so it doesn't go to waste
