I've thought about it from time to time, but...
The build is fairly free-form to start with. If you want to "play it straight" you'd basically just focus on Healing and damage prevention/buff spells anyway.
But one of the big strengths is that you can play it however you want.
A few stand out from the Paladin list though.
Hero's Defiance Paladin 1, Immediate action, if you would fall unconscious, you can instantly use a Lay on Hands to heal yourself with a bonus +1d6.
Paladin's Sacrifice Paladin 2, Immediate action, this is basically a 1-use Emergency Shield Other. Unlike Shield Other you take ALL the damage the attack would have done.
And I've heard good things about the Litany X spells.
If the others in your party are Lawful Good, then Bestow Grace of the Champion can be a decent boost.
It's also a handy spell for a single-class Oracle to have and use on themselves.