2) Inexpensive way to get to the Baths? I searched and found some roundtrip excursions for ~$140/each. Is there a less expensive way to get there? I guess chartering a boat might be less expensive since there's a bunch of us?
How many is a "bunch"? Most of the smaller boats max out at 6 people (because of licensing requirements?), but private charters are definitely the way to go. If I had 12 people, I wouldn't hesitate to book 2 private charters and have the captains coordinate an itinerary for the group. (If you find a captain you like, just ask him for recommendations for the 2nd charter. They all know each other.) Also, check to make sure that they go to the Baths, and that they can get you there in a reasonable amount of time. You'll want a boat that has engines with enough HP to get you there as quickly as possible.
You can definitely book private charters with larger vessels (e.g. Bad Kitty and its sister boat), as they advertise that they do private charters, but I'd imagine you'll have to book well in advance. If you have a dozen or 15 people or so who are willing to chip in, then I'd definitely check into the feasibility of chartering a larger vessel.
3) Arrivals in STT - we're getting in around 1:45pm, and hope to catch the 3pm ferry and not have to wait for the 5pm. We'll have some checked luggage. Any chance we'll make it, or should we plan to hangout at the airport, or perhaps consider the public ferry?
FYI, the Westin ferry leaves at 3pm and 5:30pm, not 5pm, unless they've deviated from their published schedule. If you really don't want to wait, the public ferry does leave every hour on the hour, and is very reasonably priced.
http://www.westinresortstjohn.com/transportation-into-st-john
However, keep in mind that arriving early usually means that you have to sit around and wait for your room to be ready. So don't kill yourself.
Catching the 3pm ferry is moderately aggressive timing, especially if it's on a Saturday (heaviest arrival day) during high season. Even if the timing works, folks arriving before you may have taken up all the space on the 3pm ferry. If you really want to take the 3pm ferry, your best bet is to skip the rum punch line and head straight to the Westin desk to check in. Grabbing checked luggage is a breeze because the carrousel is within a few yards of the Westin desk.
BTW, if you miss the 3pm ferry, don't fret. Yes, there's the public ferry that leaves every hour on the hour. But if you head to Crown Bay, there is a bar/restaurant right there at the dock called Tickles that serves very moderately priced food and drinks. We usually arrive at an awkward time, too, and have twice eaten a relaxed early dinner/late lunch at Tickles before taking the last ferry over to St. John. If you still have time afterwards, you can head to the little General Store next door and stock up on snacks and drinks for later that evening. But be prepared for island sticker shock.
Another bonus if you're way early for the 5:30pm ferry: You can get in line early and snag one of the open air seats up top. It's an awesome way to start your vacation.
At 5:30pm, you'll miss the big rush and have a really good chance that your room will be ready for you when you arrive.
4) Is it reasonable to skip renting a car and depend on the open air taxi's to get to/from beaches? Will they come back and pick us up if we arrange a time?
It is certainly reasonable to do this with the more popular beaches (mainly the Northern beaches). However, it's a half hour to 45 minutes to some of the beaches on the Coral Bay side (e.g Salt Pond), so figure out which makes the most sense.
While I agree that it's great to have a vehicle to putz around wherever and whenever you want, I can see how it'd be nice not having to worry about driving on the left, and who has to be the designated driver that night. (We always rent cars, but usually take taxis into Cruz Bay anyway because we all want to drink.)
If you stick to the popular beaches, you won't have to arrange a time for pick-up because there are taxis constantly milling around, even at Salt Pond Bay. (Hint: You don't have to take a "Westin" taxi. All of them will take you to the Westin for the same fee.) On the other hand, if you want to go off the beaten path, it's less convenient to rely on taxis.
