S & W:
Chartered there in 8/04 with TMM. I'll answer your questions first.
1) TMM vs Moorings - Both will work
, TMM smaller less formal with fewer boats.....but they were very capable, accommodating & flexible. We had multiple boats in our party and they made the best deal $$$$. I know another Skipper
who chartered with Moorings there & was happy too.
2) Boats - Moorings boats are standardized throughout the world so it is easy to get info. TMM will have a few of various models. Use web sites to compare...we had a Bahia
41 (very nice) & Belize 43
3) You did not say how long you are going to cruise
............Services once you leave Placencia will be minimal especially in the southern cruising area.
4) Outside vs inside the Reef - you will not miss anything inside unless you are big Divers.....if so, it is easy to arrange dive boats to pick you up in the cruising area take you outside & bring you back.
5) Big Attractions - Unlike other places you may have chartered/cruised, I'm not sure there are Big attractions...............it's a totally different experience......very underdeveloped, tiny cayes (islands) scattered throughout the cruising area..........it more about the natural beauty, wildlife, watersports, peace & quiet.
Ranguana Caye is definitely a place I would suggest to stop....mooring balls (a few but strong) and a nice little mini-resort with caretakers who offer drinks & cooked meals
. Plus the Caye is set up so you can lounge on the beach, snorkle, fish
, etc....vs other Cayes that are just sand/palm trees............or the Mangrove version (yes, two types & these tend to be buggy).
If you want a much longer version - here's info I shared with a sailnet forum member
..............hint wait for an "off hour" to access
If you have anymore questions, don't hesitate.