In the end I went with an ASUS Windows laptop. I had hoped that getting a machine which was somewhat aimed at gaming would cut down on the bloatware that came pre-installed. No such luck. I spent the first 30 minutes removing all the unnecessary programs. At least nothing looks malicious.
Then I set about the task of reinstalling software. It's actually kind of interesting what is saved client-side and what is saved on the server.
For FFXIV, pretty much all the settings are client-side. This includes things like gear sets and hot bars, in addition to all the UI and macros. I logged in to FFXIV, saw how much I would need to set up, and promptly logged out again. I'll have to tackle it a bit at a time.
For The Old Republic, at least the hotbars and key bindings are saved on the server. That saves a lot of work. The UI isn't saved, but I don't modify the base UI very much, so it shouldn't be that hard to set up again.
I think these long-term server-based games should strongly consider dividing the settings into machine-specific (graphics, sound) versus account-specific settings. And then saving the account settings on the server. It would cost some more space. But it really only needs to be downloaded at the start of the session, and saved at the end of the session.
Even just saving it as a giant blob of compressed text shouldn't be that bad. You could even take the hash of the settings and only change settings when the hash changes.
But it would make life a lot easier when moving between two machines.