Because I don't think anyone has mentioned it: an easier infinite recharge option is Linked Power + Metapower + Bestow Power + Torc of Power Preservation. The same number of feats and items as the Earth Power version, but Linked Power is an infinitely better feat than Earth Sense.
The initial cost of the Bestow Power Linked to Bestow Power is 6, reduced by one by the Torc and two by Metapower, so you spend 3 power points in the first round for 2 each over the next two rounds. The trick costs basically one feat, since Linked Power and the Torc are things you would probably want anyways. This will give you plus one power point every even round after starting to recharge, or one every round after the first with psychic meditation.
In my opinion, the best thing to do with synchronicity (other than infinite standards cheese and whatever) is to attach three of them to a mental tap tattoo with a relay using the enhanced tattoos. Get two standards each round for three rounds at the cost of one swift action.