Not having a separate generator aboard will be the dividing line for a lot of your questions/answers.
More and more of the charterers now want *everything* on the boat for a week charter. The market for simpler vessels and charterers who want to sail on boats with fewer amenities is shrinking and almost only driven by cost not preference. For a week out these days, especially with guests newer to charter, the simpler boats are a tough sell. For a 20-30% bump in cost you get much easier power monitoring, AC,flat screen tv's, microwave oven etc.and will make the decision a simple cost comparison.
In your case I would concentrate on the best battery bank you can afford, high output engine charging system, certainly a dedicated isolated starting battery, efficient refrigeration, an inverter system with an easy to monitor panel, any solar assist you can add, well maintained sails and running rigging, top notch bedding, excellent hatches and ports, multiple awning options, comfortable cockpit seating, the best chart plotter you can find, perfectionist engine maintenance, a clean bottom and having a Bristol condition look to the whole vessel.
Nothing wrong with thoughtful upgraded Simple!
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