I’ve been using Linux for maybe 8 years before getting a Mac and found it to be great to use pretty much immediately. So there’s not really much I can tell you here. Except maybe to install the GNU coreutils from homebrew (and that itself if you don’t have it yet), the ones it comes with suck.
I don’t think there is a way to download Xcode without an Apple ID. The App Store also needs one though you could get by without that. You could just make the account only for downloading Xcode and only sign in in the browser for it, I suppose.
Edit: Oh yeah, get Mac Mouse Fix if you plan on using it with a normal mouse. The standard scrolling behavior is abysmal.
If Google is the only thing holding up the non-Apple web browsers, maybe then this will lead to scaling down the insane scope of the web standards so it becomes reasonable to implement and maintain a browser for non-megacorps.
Wishful thinking, but hey.