It depends especially on the level of comfort and facilities on board you are looking for:
In general, cruises include: accommodation in cabin with private facilities, guided excursions with professional Licensed bilingual guide, transfers within Galapagos (on cruise dates), Airport assistance, all meals on board while cruising, drinking water, tea, coffee.
Luxury and First class cruises also include usage of snorkeling equipment and most of them have sea-kayaks on board for guests. Some Luxury class cruises also include Wet suits and others and First class cruises have them available for rent on board.
Midrange and Economy class cruises have snorkeling equipment and Wet suits available for rent on board (in cash).
For domestic flights to/from Galapagos, each passenger is allowed to bring one piece of luggage of no more than 20 kilos plus one hand luggage or backpack of no more than 10 kilos. Each passenger can also brink on plane’s cabin 1 small purse, handbag or camera-bag.
If excess on luggage occurs, the fee will be charged and paid directly at airline’s counter at the moment of check-in after checking space on cargo area on the plane to Galapagos.