Mouse and keyboard or controller and which kind of skill set up/bar etc?

[Kraniel]

I've never tried to use the controller so i can't say for sure, but i've heard it's actually quite good.

As for KBM, i have a "classic" gaming mouse with only 2 thumb buttons, so nothing too crazy. I use one thumb button to target, and the other to focus the target.

I have 3 hotbars with the following bindings :
1 2 3 4 5 q e r f c
With CTRL : 1 2 3 4 q e r f c
With ALT : 1 2 3 4 q e r f c
With LSHIFT : q e r f

Although i have to admit the game sometimes makes me wish i had a mouse with 10 thumb buttons, at least this setup allows me to move + use actions at the same time (once your muscle memory has worked out all your keybinds, it gets natural and you hit them automatically).
Try to keep things logical for your brain as well. For example, i know i use Swiftcast + Raise a lot as a healer, so i bound them to ALT+R and ALT+E, which allowed me to remember this specific combination pretty fast.

So yeah, if unlike me you have a super high-tech mouse, i would recommend using it to its fullest, because depending on the class you will have a ton of skills to manage when you're 80.
Also, don't use keybindings for stuff that you don't need in fights (like mounts, or buffs that are activated only once at the beginning of a dungeon).

Other players will probably have better advice to give, but i hope at least this gave you a bit of information to work with