Re: Internal power in tai chi chuan
I think William Chen would be a good place to start, he will certainly put you in the right direction. And if you choose in the future you can always explore/meet/feel other people from different lineages and see how they compare.
One think i would suggest, and this is just from my personal experience and opinion, don't get tied to the form only think of it as a vehicle to develop the taiji body (aiki body), nothing more. Yes there are techniques throughout the form but don't become a slave to them.