Backs are high. Double check you are okay with this as it may limit use on the side having the stools. Also you will be looking at the backs when standing on the other side. Stools are okay but this is an opportunity to add some color to the white kitchen (assuming you might want color). Regardless all will work but I like #3 the best.

They would all work for a transitional style. Post a photo of your space. Does your backspalsh run vertically or horizontally? Do you have pendent lights? #3 is a simpler style and #1 is more interesting, but it really depends on everything else in the space. What is the flooring material? How many stools and how big is the island?