I think it would be a very interesting time to add popular maps from every previous title in the series.
Why?
It’s a great way to market the title of this release! Infinite! The possibilities are Endless.
Which Maps?
Guardian comes to mind. Think sweat. Think nostalgia. Think limitlessly.
When?
Progressively releasing Map Batches (2 to 6+ Maps) with Updates/Expansions would be excellent.
What’s the point?
The best way to put it, so we can “Finish the Fight.”
At this point 343 is charging an arm and leg for the most basic of armor coatings and armor pieces that were copied and pasted from previous titles… I hate to imagine home much they are going to charge for maps from previous titles haha.
Oh I’m certain Valhalla will eventually find its way into Infinite. I think it’s a law for Halo games now.
Certainly a valid fear. However, it seems that the current pricing is temporarily higher than standard pricing will be. I feel that maps will not be a behind a pay wall because everyone needs a copy of the map to play together. That is not the same with cosmetics. I believe that all of the added maps and modes will be free for this reason.
Right? Halo Staples. I wouldn’t mind seeing more of the less played maps as well though! Something to give us nostalgia-out-of-nowhere kinda maps I’m hoping for.
Valhalla? no way Blood Gulch it the true King.
XD haha it will have a new name for sure when it drops in Infinite tho 
I’d play lockout 24/7
Yes!! Lockout is one of the greatest possible maps to add to Infinite. The paths are so diverse and interesting that it would be amazing to see new tactics with the new capabilities of Infinite Multiplayer.
Powerhouse and Hang 'Em High please!
Grappling around Powerhouse would be really fun. Great map.
The high visibility of Hang 'Em High would make intense games with all of the new weapons too! Halo 1 maps are very unique.
For real bro, grapple hooking around the two story buildings with the bridges has some really fun possibilities!
Same with HEH now I think about it, all those bridges and platforms will make for some interesting grapple hook and repulser moves.
Reach has some absolutely fantastic maps with great verticality or wide spaces.
Halo Reach has a lot of cool maps really, Swordbase is awesome, Countdown is awesome, Boardwalk is awesome, lots of good stuff that Infinite can remake in it’s own style!