Questions about Paladin Soloing

Hey guys,
I used to play on this server when it was still called Molten-WoW, and one of the things I enjoyed most doing, was soloing content on my DK.
I'm talking about Heroic\normal instances, raid bosses, achievements, and generally just challenging myself with ridiculous things to do when bored.

Examples of sh1t iv'e done:
https://www.youtube.com/watch?v=aDLNhtxeFAM
https://www.youtube.com/watch?v=TG6noA8BMTs
https://www.youtube.com/watch?v=ScQsI9cGnsY
https://www.youtube.com/watch?v=yikfPHMCMJc

Was wondering, to what extent similar things are possible on a Pally, assuming I master the class in terms of skill and have decent (5-6k GS) gear for both ret\prot?