The basics I want on my bar for easy access

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.

SCH Layout 6.55 (Not 7.0-Able)
LT>RT remapped from Set 8 Left to Set 8 Right, only right half of Set 8 is used
Set 1 - Primary Heals/CDs ; Set 2 - Utility + Raise ; Set 8 - DPS / Heal CDs

from bun boss video

Endwalker Lvl90 Scholar

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)

##For General Content (not tested with Extreme/Savage)

I have trouble remembering what's in my 2nd crossbar, so I always copy 2 to 3. Until I decided to play Scholar XD

My scholar crosshotbar.

Just copied Nanaki's

Gain Seraphism. (Teleport as placeholder.)

Healer icon = Seraphism

Ally-targeted abilities are placed on the D-pad because you will already be using the D-pad to scroll through the party list and select your target. Most GCDs, untargeted buffs/heals, and mobility tools are placed on the face buttons so they are easy to access while moving.

Core damage actions are placed on the RT and RT>LT bars, including Aetherflow and Dissipation. Lossless faerie heals are placed on the RT and RT>LT bars since they should be prioritized over "lossy" Aetherflow and GCD heals. The LT and LT>RT bars mostly consist of lossy healing actions and related abilities.