I think my AST bars are less crowded than WHM, but both play just fine on PS4. I have a separate bar for DPS moves, and I keep "circumstantial" moves on a third bar. Stuff like Stoneskin II, Repose, Protect, Noct/Diurnal stances, etc.

Any moves that have long CDs that I don't have on my first hotbar I keep on a horizontal bar under my crossbars, so I can monitor whether or not they are off CD.

You can also set up holding down R2+L2 and L2+R2 to reveal half of another hotbar without having to swap them.