You're spoilt for choice as far as venues are concerned...
A traditional wedding in a 14th-century French cloister; a tropical wedding in one of the many botanic gardens, with hibiscus plants and parrots all around; a Junkanoo street parade wedding with a carnival atmosphere (think Baha Men!); a wedding on a boat, on the the beach or in the water.
Whatever takes your fancy!
To help you organise your wedding, get a wedding planner in the Bahamas (see the Tourist Office for contact details) or see one of the big hotels who will know about special events taking place.