I personally put any actions that I care about the recast timers for (or just stuff I always use) on my first action bar, which is generally what's always visible.
All TP moves and related go on action bar 2. In general I won't actually use this bar though because I have all my TP moves macroed, and then macroed again onto G-keys. I also have a couple other abilities here that I /might/ use occasionally (like Defender, because the recast is so long).
All my spells go on my third action bar, and again I won't really use this bar because I have all my spells macroed, and then macroed again onto G-keys.
I'm not logged in to check but I'm pretty sure my action bar goes:
Bar 1:
1) Light Slash
2) Guard
3) Aegis Boon II
4) Deflection
5) Emulate
6) War Drum
7) Sentinel II
8) Heavy Stab
9) Siphon MP II
0) Obsess II
(Heavy Stab is my standard attack while playing as Gladiator, but it's on "8" instead of 1 because 8 is directly above the "I" key, which my hand is always on anyway because of the camera controls, works out much better than using "1" imo.)Bar 2: (Order generally doesn't matter, macros will work as long as they're on the bar somewhere)
?) Defender
?) Punishing Barbs / Cadence
?) Riot Blade (
G9)
?) Spinstroke II (
G8)
?) Howling Vortex (
G11)
?) Circle Blade II (
G7)
?) Luminous Spire (
G12)
Bar 3:
?) Sacrifice II (
G4 - Cure Self /
G1 - Cure Subtarget)
?) Ressurect
?) Protect
?) Shell
?) Provoke II (
G16 - Voke Current Target /
G13 - Voke Subtarget)
?) Taunt (
G17 - Voke Current Target /
G14 - Voke Subtarget)
"G Keys" for anyone wondering are an extra set of keys on the left side of a Logitech G-Series Keyboard that can be programmed to press any other combination of keys on your keyboard. I use the keys to hit macros (CTRL+1, etc) which use my standard abilities. It basically gives me one-touch access to abilities on my second and third action bars without having to switch bars:

Despite all this, my number one UI change request is for SE to
make all three action bars visible and usable at once. It would make things so much easier.