Not at all. There is no need for you to follow any set itinerary, unless time is very short and you must plan everything down to the minute.
Where time is not an issue, there is a fair amount of flexibility built into any charter, although cruise logistics require that you allow sufficient time to get from your "pick-up port" to your "drop-off port." Experience has taught that it is much better to choose a less ambitious style of itinerary, and actually slow down and see the coastline, rather than rush to see all of the sites, and miss that leisurely pace, where you are able to start relaxing and taking in your surroundings just a little better.
You captain is always the best person to approach for a run-down of the day ahead. He is keeping an eye on weather around the clock, and will give an acurate estimate of cruising time - or sailing time as the case may be -- which will enable your cruise itinerary to flow in the manner you require.