At least UMD is a skill worth investing feats in. If you're going to be the party's sole spellcaster, adding the ability to use all kinds of wands, staves, and scrolls will make a welcome addition to the party's spellcasting potential. And UMD can get downright broken if you use it to wield or activate magic items that have specialized requirements. Afaict the main feats of choice to get UMD as a class skill appear to be Apprentice (Spellcaster, with another Paladin as mentor), Aereni Focus, and Cosmopolitan. If you have no better options Skill Knowledge will work too.
Alternatively you can prestige into Knight of the Weave if you want.