When comparing Arc vs Paper, the Slant community recommends Arc for most people. In the question“What are the best Gnome Shell themes?” Arc is ranked 1st while Paper is ranked 4th.
Ranked in these QuestionsQuestion Ranking
Pro Customizable to dark or light themes
Pro Has both GTK2 and GTK 3 support
Users will be able to match their gtk2 and gtk3 themes easily due to Arc supporting both.
Pro Supports gnome-shell
Pro Available firefox and chromium themes
There are matching themes for Firefox and Chromium for those that want to have a fully matched looking environment.
Pro Really clean and nice-looking
Pro Flat and colorful design
The look of this theme is inspired by Material Design.
Pro Does total makeover of your computer
It's a complete theme, with custom icons, GTK, cursors, Gnome Shell.
Con Bleak font colors that cause eye strain
The font color in Arc and Arc-Darker is not black, but lightgray
after prolonged usage, it becomes apparent that this font color, combined with white backgrounds causes too much eye strain
Con Has some contrast issues
The theme is a low contrast theme so it really depends on the screen brightness if you see borders or the text, some elements don't even have borders - this makes the theme barely usable for portable devices.
Con There is jumpy behavior when switching from window to window
You can notice jumpy behavior when switching from a forefront window to window behind it. Both windows jump a little which can slightly disrupt normal working flow.