The BVI are awesome, but as an East coaster (US) it is an easy trip for us, been there 5 times. I am exactly the opposite of you Nibsoe. I am contemplating the long trek to Tahiti and would love to cruise the Whitsundays someday. If you decide to come out to the BVI know that Christmas week is the most popular and expensive. I have not been there at that time for that reason but I have been there in both the high, mid and low season. I am a mid season kind of person. A lot of stuff is closed in low season, the weather is not great and it has an abandoned feeling in some locals. The high season is very crowded, which some people love. The night life is awesome. I like mid season because it is a good compromise. Plus I cant stay up that late anymore

. I do not want to discourage a Christmas trip it will be great, but busy.
About you side of the world. I just recently started a topic asking for advice for chartering in Tahiti. I would be going in their high season , July. It is just how it works out, Although I do not think crowded anchorages will be a problem because there are probably only 50 boats for charter in Tahiti. Here is what I learned, unfortunatly I haver not gotten feed back from two forums I have posted on yet, so if anyone can advise please do so.
On Raiatea the three main players from what I found , Moorings (most expensive from my quote) , Sun Sail and Tahiti Yacht Charters (least expensive). The islands of Raitea, Taha, Bora Bora and Huahine are all accessible in a 7-10 day charter. Very few guides are written on the area. I have the one from the moorings, very brief and one other from Charlies Charts really for cruisers but some good info. In the end I found info scarce.