playnite-library-psn VS GlosSI-Integration-Playnite

You can use tags, some library plugins can tag those games automatically (or there are plans like https://github.com/XenorPLxx/playnite-library-psn/issues/8). The main Xbox library add-on doesn't add game pass games unless you run them at least once.

True, but it's still there. I'm using it. https://github.com/XenorPLxx/playnite-library-psn

There's a program called glossi. It basically lets you utilize steam's controller bindings for your entire computer. But then there's a Playnite add-on under the generic add-ons called glossi intergration. You'll want to add it via Playnite, but there's a github page with the full details here.

Optional things I recommend is browsing Playnite addons for fullscreen themes you like, as that always gives your deck some versatility. I am also looking into the whole ludusavi plugin to be able to create my own cloud for non-Steam games, as well as the GloSI plugin which I haven't had time to explore yet. AutoSave for Playnite which works with Ludusavi also seems to be a winner.