If you have a big island that can accommodate many people, consider using full benches. The benches can be with or without backing to allow for more comfortable seating.
For those remodeling and looking for an "open" feel where perhaps the wall or half wall separating the kitchen and the dining room is taken down, a strategically placed island acts as a subtle room divider mentally separating the kitchen from the dining room but with a much more open feel.
Safety First! You are better off without it if you are using up all the free space in the room. Your kitchen should be spacious and you should never feel restricted in your movement - in fact it can be dangerous if you are. Yes, a kitchen island is good to have, but not if your safety and freedom of movement are compromised to accommodate it.
Maximize natural light by having windows and skylights, and keep kitchen wall surfaces light in color to reflect daylight. Custom kitchen islands work great by using pendant or recessed fixtures to direct light onto the kitchen island and other work areas. Electrical codes will likely require that electrical outlets be located on the sides of fixed kitchen islands, not on the top, to prevent electrical shock.
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