Cool to see stuff like this... that said, personally I've really gotten into basing most of my validation around zod... this works with hono/zod-openapi as well as client validation integration, so I'm able to get a lot of usage out of the same tools on both the client and server usage.
For server-side, with JS/TS I've gone heavy in with hono, recently used the zod + openapi integration, which has been very nice to use. I've also used C# with FastEndpoints library, which has also been very nice.
Client side, currently working with Mantine component library, though have used MUI a lot as well... for forms, I've used React + React-Hook-Form and zod indegration. Creating modest wrappers around form field elements in order to present error states and helper messages cleanly.
Not to detract from this Vue3 approach, just pointing out what I've used and that zod in particular has made things pretty nice all around, not just on the client.
Same, I have been using Zod heavily for the past year.
Hono looks really cool, but I got too comfortable with NestJS to make the jump :D
I should really give it a try though
I'd say it (Hono) is about half a step above Oak or Koa in that it's a similar pattern with a "standard" entry that works pretty well cross-environment... Native for Deno and Cloudflare (I think Bun too) and a small shim for Node.js, the only hard-ish part is there's some inconsistency between publishing of different parts between npm and jspm, also some of the environment specific modules were a bit more difficult to work out (at least in deno) as a result.
I've toyed with CF Workers/Pages deployments with Turso and D1... I want to like the CF hosting stuff, but have a few times had issues where I'm actively developing and the test environment deployments bork.
I haven't used Next/Nest enough to fairly comment on them. I'm not really a fan of page based routing, not to mention for apps, I don't really care about SEO, so have been fine with SPA React.