I like your hi-tech design!
I have one who prefers tile to carpeting, when it's warm. The other one? F'get about it! She's purely a couch potato. She'll even thieve a blanket from ya!
Outside in summer? If there's a breeze it doesn't matter. But on a hot sunny day, yeah. They like shade, too!
Kids may "seem" warmer or act warmer than us because they move around more.
But normal kids run 98.6, just like we do.