I show Cross Hotbar 3 (Left) with both of the expanded trigger controls, so you can easily add in another 8 actions if you prefer, I use XHB 8 as a shared bar between all classes for traversal and general actions outside of combat. Role actions are consistent among my layouts, and so are general actions. The macro icon is a placeholder for a Tincture/Gemdraught.

Pot goes on Bar 3 Down D-Pad Raise uses Macro

Just copied Nanaki's

MMO mouse setup with modifiers.

for each job, I create a "hotbar" that is basically a monitor for cooldowns/any spell/skill I want to see the status of; I also have a hotbar with Role spells & skills, and, Sprint. I would add Second Wind in the missing slot. I use Hotbars 2 & 10 but you can use any Hotbars you want.

for RDM, there are only 6 spells, so you could put them all on 1 column; I don't do this because of how I have my UI setup to accommodate multiple job setups.

Hotbar 1: White mana on the left side, black mana on the right side. Single target above, AoEs below. Both/neutral down the middle. I used to put acceleration on Hotbar 3, but it's better this way for quick succession to the relevant actions.

Hotbar 2 (ctrl): The 1-2-3 melee combo on top. I usually have my gap close/make on those two middle positions. Sleep, lucid, cure, and the DPS buff are just rollovers from my old hotbar as Summoner, my first job, and that was before I put more thought into hotbar setups. AoE and run+gun spenders on the bottom row.

Keybinds for those interested.

I use an mmo mouse so 1-6 on all bars are pressed on the mouse, uisng shift and ctrl for bar 2 and 3. The latter 6 on all bars are pressed uisng the keyboard and shift/ctrl.

this layout works for levelling from RDM unlock through Dawntrail. main crossbar is your single target spells & burst rotation, and the 2nd has your AOE spells

Pot goes on Bar 3 Down D-Pad Raise uses Macro

Lvl 100 Red Mage XHB made by a ps5 player

The VerHotbar

I created my chotbars to be comfortable, practical, and aesthetic.(to me anyway) Nearly all same/similar skills are in the same position across all jobs/roles while allowing for as little finger gymnastics as possible.

My XHB is split between chotbars 2(left) and 7(right)

Hotbars for Lv60 Dragoon.

Lv60 Warrior Hotbars

Hotbars for Lv60 Dark Knight.

Lv60 Paladin Hotbars

Hotbars for Lv50 Astrologian.

Hotbars for Lv60 Ninja.

Hotbars for Lv50 Machinist.

Hotbars for Lv50 Gunbreaker.

Hotbars for Lv50 Scholar.

Hotbars for Lv50 Summoner.

Hotbars for Lv60 Samurai.

Hotbars for Lv60 Black Mage.