Hmmm.
PLD: Proper use of Cover (useful in Coil or WP). Balance on-GCD stun timing with enmity gain and remain aware of Diminishing Returns (Stuns are very effective on Trash). Likewise, Flash's "Blind" Diminishing Returns. Use of Spirits Within for Silences (No DR for you, but need to be aware of it if you have Bards in the party. Long animation means you need to anticipate cast times). Proper use of Stoneskin (On-GCD very high mitigation in certain boss fights, but results in less enmity gained. Interruptable if you take a certain percentage of incoming damage during the cast). Use of the Riot Blade combo to regenerate MP used in Flash spam (Mainly Speed Runs not Boss fights, though I've used it before in AK Boss #3 for example due to Stoneskin spam!). Ability anticipation for pre-emptive activation of proper cooldowns (No sense using Bulwark versus Magic Damage!). Swapping into Sword-Oath for certain Phases (Titan Heart?). Remembering to NEVER EVER USE AWARENESS EVER due to the brokenness of it preventing Critical Healing on you... the list goes on!
Paladin's Weaponskill rotation is very basic, but it has a lot of flavour or "utility" abilities that can sometimes make or break a fight.
The "fun" for me comes from the constant battle for hate, and jumping around the dungeon maps like a giant heavilly-armoured kangaroo.
I tend to queue for DF dungeon runs and get players with very very random ability. Carrying a "bad" group through a dungeon - Fantastic fun. Never letting an "excellent DPS" group pull hate from me? Intense, but brilliant run. Managing to finish off a Boss whenever the Healer died halfway through due to no fault of my own? 'Mazin craic.
PLD = Keep Hate, Be tough to kill, and Instantly Adapt to whatever random situation crops up.
(Occasionally you just plain run out of Cooldowns or HP, but that's what the respawn button is for!)
Only problem is that I'm constantly getting dragged into random Coil PUGs now...