Smite Evil (Ex)
Remains horribly worded. Split it into two abilities, one always-on, the other activated.

Zeal (Ex) can be the half her class level (min 1) bonus damage against evil creatures she hits.

Smite Evil (Ex) would then be the activated ability. This makes "an additional use" and the like far easier to write. Oh, and how about a smite every odd level? :)

Divine Grace (Ex) -- make capped by at least your Paladin level. At level 20, having more than 30 Charisma is quite possible! And +2 to all saves is not worth a 2 level dip.

Lay on Hands (Su) -- how about (Charisma)*(Paladin level) healed per use, and 1 use per 2 Paladin levels? It does make it worse (in that you cannot efficiently heal 1 point of damage), but total amount healed now grows quadradically, so it scales better. And "lay on hands" is not "pool of extra HP you have to keep track of", but rather "boom, full health sucka".

Then "uses of lay on hands" and "uses of smite" can both be resources we can spend on other abilities.

Special Mount (Ex) -- We could split this into a whole host of abilities which involves summoning Holy Implements to aid in her quest. A Holy Mount could be one such element -- Holy Swords, Holy Armor, Holy Advisors could also be added.

Purify (Su) -- So, someone is hit by a poison, and is reduced to -5 HP by it. Purify then removes the damage? What if the target died by poison?

If we go with "Lay on Hands" is X/day thing, Purify could read "expend an extra use of Lay on Hands"?

We should also make the Paladin immune to all diseases and poisons at some point.

Consecrated Aura (Su) -- Make it a standard action and a use of Lay on Hands instead of a free action to recreated: then you can have a Paladin and an Evil Cleric fighting against each other with raw holy energy...

Castigating Gaze (Su) -- so a Paladin walking through a town will blind a non-trivial percentage of people?

Touch of Life (Sp) -- while nice, gaining the ability to cast a 9th level spell at 17th level is far weaker of a class feature than a spellcaster gains. Being able to do it once per week...

If you changed it to "as a standard action", now we are talking awesome.