skulls in halo infinite campaign

i saw on the reveal that skulls were one of the “area collectibles”. this means that like in Halo 3 each level has skulls to collect. being a SLASO player this is really exciting to me.
WHAT ARE YOUR THOUGHTS?

Can we even change the difficulty of the campaign? I haven’t heard anything about it. Pretty cool they have several types of collectibles though

I guess it depends on how the campaign is presented. Can we replay the campaign? Will it be like Destiny, when after one mission is over, it goes away forever? I hope there’s some kind of menu like MCC where you can pick certain places to replay, with skulls and difficulties and options.

But that sounds like a neat addition that will let me play Infinite longer, so I’m all for it.