Well, in my personal opinion...
Samsung is almost as bad as Apple is when it comes to shady business tactics. They also load their phones with a crapton of bloatware, that you'll likely never use, but can never uninstall. Think note-taking apps, fitness apps, camera apps, all that crap. It's excessive, and annoying, and while you won't have this problem on newer phones, on their older stuff it would cause your internal memory to be full in notime. For that reason alone, I never buy Samsung anymore.
LG is pretty solid, but also suffers from the above problem. Less so, but still pretty annoying. They have extremely nice camera's though. The camera on my old G4 was amazing.
Nokia is also making Android phones, and I'm pretty fucking pleased with mine. They offer a nice price/quality balance. Although the specs aren't as high-end as other flagships, they are still decent enough for me to do whatever I want without much problem. Their buildquality is pretty awesome too. They're not the best phones around, but they cost less than 400 euros.
Major sellingpoint for Nokia, however, is the AndroidOne program. This means that they ship their phones with a bare, stock version of Android, which is usually also one of the first to update. If you don't really care much for high-end hardware, make sure to look for phones in this program (others have this too, besides Nokia).
I personally don't trust those Chinese phones, Xiaomi and Huawei. Cheap as hell, while still having decent specs, but I don't know... I've heard stuff about spyware on the things, and I figured I wouldn't want to take the risk if there's a equally low priced alternative on the market with the same specs. That is, of course, under the assumption that other phones don't have spyware as well.
OnePlus is still a decent competitor. I've never owned one myself, but my father, mother AND brother all do. They seem pretty satisfied with theirs, so...