We have posts! After a week of almost zero activity on the loft project, the metal posts finally arrived yesterday and were installed today. We realized that these posts will get a lot of abuse as the boys climb in and out of the loft, so we decided to go with steel instead of wood (in part because it will make it easier to firmly anchor the posts to the loft). They look very industrial now, but once they're painted white to match the wood railing, I think they'll look fine. And they are indeed very strong and very well anchored.
This is one of the pre-finished cork planks that will make up the floor in the loft.
Back when we did the remodel, we considered using cork floor in a couple places before going with hardwoods (almost) everywhere. Our architects have this same cork flooring in their conference room.