Is there any way to move window buttons to the right of the top bar OR back to the windows itself?

[dr460nf1r3]

Just do a rightclick on the plasmoids (the widgets) to edit settings - the top bar has 3 of those.
There are settings to disable the automatic removal of the window buttons on maximize. Also you can do a rightclick on the Latte panel (where the plasmoids are located on) and reorder/remove them.