If you really want to go all out for healing with a paladin then go for a Hospitaler with an oath of charity. The hospitaler gives you a pool of channel energy that does not use lay on hand. The oath of charity gives you two advantages. First it allows you to heal 50% more with your lay on hand, when you target others. The downside is you only heal 50% of the damage you normally would when healing yourself with lay on hands. Second but more importantly you can change your mercies on a daily basis, but you lose divine bond.
Make sure you have wands of cure light wounds and a few scrolls with condition removal spells and you should be good. Paladins get lesser restoration as a first level spell so that will actually help a lot.
Paladins are one of the best tanks in the game so that is pretty well covered just by being a paladin.
I would suggest using your feats for combat and not to boost your healing. If you go with my suggestions you will have the healing covered, but getting fewer smites is going to weaken your combat. Go with the normal combat feats like power attack and such.