Originally Posted by Striker
Which ones are you referring to? The bad ones I had the most distaste for are ones that heavily rely on lifts and shield doors. Or just bad design (Isolation, Orbital). Maps like Zealot, Powerhouse, and Pit are good, although in comparison to the ones in Halo 2 they are really mediocre.
All the default maps will get upscaled but they also are making 6 re-made ones in another engine.
Maybe "many" wasn't the right word to use literally. As simple ports, there are very few I'd be able to think of that would fit because they're always built for the game they're in. I try to think of them as conceptual pieces though, and some of the general layouts had that sort of potential. None are coming to mind but the ones you mentioned would work with some tweaks.
The main difference between the early game maps and the latter ones was that the maps stopped emphasizing vertical advantages, overlapping paths, and and different movement options (such as teleporters and large man cannons). The maps ended up flatter and more linear and then Sprint stretched them out even further.