Land based tour, how many days on each Island

I am researching a trip for early Dec 2025. We definitely want to do a land based tour a s will have 10 nights on the Galápagos Islands. We want to visit San Cristobel, Isabela and Santa Cruz but I am unsure how many nights to do on each and if we do a 3/4 combo which one we should chose to do 4 nights on. We are going for the wildlife mainly, although we don’t have specific birds we want to see. I would like to snorkel, see penguins, the seabirds that are around at that time. Iguanas, turtles, sharks, sea lions and of course tortoise.

We can fly into Quito or Guayaquil or into one and out of the other to connect to / from the Galápagos. I am not sure which order to do the islands in either as I think we can fly into one and out of another to minimise travel between islands. One of us is not too good on boats and so anything that reduces ferry time will be good as I understand the crossings can be rough. Is it possible to fly between the islands?

Amy advice or opinions much appreciated!