1. The way I've been thinking about it now is similar to how I use autolayout in Figma. Simple x/y is convenient for a very first rough draft. Then I'll refine my design by making components and adding autolayout as needed once the project grows or I want to collab with somebody. Similarly, Noya will support putting components in "stacks" and other layouts (some of the built-in components do this already) that translate cleanly to e.g. flexbox. The hump is definitely there, but I think we can make it relatively pain-free. Since code export is configurable on a per-design-system basis, a company can also adjust the code/config export to match what they do in production.
2. We'd definitely be open to it, but it might be difficult/impossible to make it a good UX. We render actual React components from a company's component library in the browser DOM, whereas Figma renders shapes on a webgl canvas. It might be possible to mix and match with Figma widgets in some way, but would probably be janky. Could still be worth trying though!