If you're looking for easy and forgiving jobs, MCH and DNC are your best options. Both are extremely trivial in terms of rotations and have very few buttons. BRD is easy too, but you have a couple of timers to pay attention to.

If you're strictly a melee player, it makes very little difference. MNK is probably the one with the most straightforward rotation, but if you mess it up you loose a lot of damage and it's more reliant on positionals.