Casual Endgame Activities

Sorry if this question has been asked, all the similar posts I can find are centered mainly around gearing/mythics/raid content.

What should I be doing weekly/daily if I want to focus on:

* Maxing reputation with the different factions * Levelling up profession knowledge * Farming transmogs * Farming mounts * Farming pets * What do you get from doing Prey's other than gear upgrades? * Is there any reason at all to do heroic dungeons? They seem completely irrelevant due to Mythic/Devles? * Is the best way of getting PvP gear/transmogs just queueing for random arenas/battlegrounds?

Thanks in advance.