A lot of the talents serve a dual nature, reflecting the nature of the paladin class itself, to protect itself as well as its allies so some of these talents will come down to pure preference depending on playstyle.
Here are the bones of the choices we’ll be working with: http://mop.wowhead.com/mists-of-pandaria-talent-calculator#lxVN
I recommend Pursuit of Justice with Speed of Light in close second place. While the other two choices have the stronger speed boost, they’re a little more conditional, being reliant on a cooldown for one and reliant on you having your Judgement up and an enemy in range to use it on for the second. While Pursuit is the weakest of the three (as you’ll probably be spending Holy Power fairly rapidly), the fact that it’s up all the time means that likely, you’ll get the most out of it in the long run.
At 30, I’d recommend either Fist of Justice or Burden of Guilt. While Burden of Guilt can be useful, being a near constant slow on your primary target, if a mob gets away from you, you’d probably rather CC them and taunt them back before the slowing effect can really be helpful. Burden still has its place as Fist of Justice only knocks the cooldown on your Hammer by 50% so one can argue that taking Burden provides you with the best of both worlds.
At 45, I’d recommend Eternal Flame. Sacred Shield probably won’t be that effective as you likely won’t be standing there healing as a tank and Selfless Healer may or may not be useful based on your personal mana situation. But Eternal Flame’s Holy Power cost means that you can pretty much guarantee that you’ll be able to use it to save you or someone else when you need it.
At 60, I’d recommend Clemency. Unbreakable Spirit is definitely a very strong contender, reducing the cooldowns of your stronger abilities but I think Clemency edges it out with the ability to use something like Hand of Protection twice in a row to potentially save two people instead of saving one now and one three minutes from now.
At 75, Divine Purpose is a shoe-in. Holy Avenger can be useful for those fights where a really big spike is needed but overall, Divine Purpose will provide you with a lot more Holy Power usage over time than any of the other choices, provided that you use up the charges as you get them.
At 90, the obvious choice is Holy Prism. It’s adaptable nature makes it a fit for almost all situations, whether you need some more aoe damage, more aoe healing, more single target damage, or more single target healing. The fact that it’s got a 20s cooldown compared to the other 1m cooldowns as well as the fact that it delivers all of that damage or healing up front instead of slowly over time makes it the clear winner.