I've been Controller (DS3 > Xbone > DS4) since binding coil. It's all down to your preference and how much time you wanna put in (Re-learning takes time, I mean). It feels more comfortable for me.

In the brief period (Omega Alphascape) that I did try Keyboard and Mouse on FFXIV, I could only stand to use a 12-button (Naga,Scimitar, etc).

Then even within groups of input, like above, some keyboard players use 12button mice, some use orbweaver systems, and then controller players some use WXHB, some use Combination L2/R2 for different hotbars.