So; well development is kinda crazy and stupid.
Angular and React seen the most popular at the moment, and I'd personally lean towards React (even though I haven't gotten to use it).
Angular is/was just a huge framework that bloats your webpage. I see it like using C++ and using namespace std for just a "hello world" when C would get the job done (and size matters when you have to push it over the network!) So if this is a small not complicated site, please skip Angular (unless it's gotten better over the last 6? versions since I got stuck with it)
React, is apparently only part it a MVC framework/model, which you'll read about when researching and reading about React. So you still might need other libraries to support it, such as Bootstrap(made by Twitter?) And Redux(funnily enough as fat as Angular is, I've seen this pulled in for Angular as well, even though it was mainly built for React)
Bootstrap, from what I've been told, basically makes dealing with CSS a much less painful ordeal. I don't know if it relates to QT, but it might help.
As for auth, I don't have much experience in that. I can only suggest to not, I repeat, do not use JWT*. Especially for the use case you mentioned.
*http://cryto.net/~joepie91/blog/2016/06/19/stop-using-jwt-for-sessions-part-2-why-your-solution-doesnt-work/
I'm sorry I couldn't be much more help. I'm just really sour about how terrible JS is and it's ridiculous number of new frameworks and shiny balls that come out on like a daily basis; all to fix JS, HTML, and CSS shortcomings. Web components and web assembly look promising though ?