You can cap charms from rare spawns incredibly easily, 2-3 per kill and they're shared loot, so each person in your party can loot them if you're in one.
I think I've earned around 130 charms in the past 3-4 days and the only dailies I've done were pet battle ones once (which are also very viable now charms and VP are a guaranteed reward from the daily pandaria trainers).
Also earned over 700 VP on day one without touching LFR or Dungeons, just 3 H-scenarios, pet battles and the weekly barrens quest.
They seem to have made VP and Charms trivial to earn your weekly cap, starting to wish lesser charms had an alternative thing to be spent on since I'm now over the 1k mark and earning far more than I can spend a week just by doing pet battles, let alone the rare spawns I regularly kill or when a new daily hub is out.
Worried they might have gone a bit too far with making it easy to grind out, but I think it's better to learn on things being "too easy" to cap on if it means alts are actually something you have time to play.