I would go with whatever you like for the island. The only thing I would personally stay away from is trying to match the floor to the island stain. But a dark stain you you show in the bottom picture would be great!

You have a wonderful, huge deck in a beautiful backyard. You would need to do the benches as well as the railing and steps. If it were mine, I would clean it well then put on a protective coating. That alone will enhance the color and protect it from mildew and wear and tear. You have a lot of deck to cover and if you do a stain, it will NOT be permanent. It doesn't matter which type you purchase and use, it will need to be touched up and/or restained at least every few years and that is if it is applied perfectly. If you decide to deepen or change the color later, you can do it after you've sealed it. If you darken the color with stain and decide in a few years that you wish you hadn't, stripping it all off would be a nightmare and would damage your wood. A colorful unbrella for your table, plants in pots, and some decorative throw pillows would really finish it all off. We purchase our house with a dark stained deck on it and I HATE it. It is hot and the maintenance is a killer.

The home has a great look. But before you look to remodel you need to look to the furnishings you will put into it. Many people buy a house, paint the walls redo the floors, change the kitchen, etc., then look to purchase furnishings. So think about that first. What do you have now that you will keep for the long term. And what do you plan to purchase new. Have a clear plan as to what these items are, keeping in mind colors, style, and patterns. Then look at floor color, rugs, lighting fixtures and furniture. The wrong order will ultimately make you frustrated.

Of course...but do they have to be raw stained wood?....this finish is all by itself in the room and unnecessarily dictates other choices...nothing else in you space is rustic...it just feels out of sync...and the dark color horizontally makes the ceiling look lower....