I design day in, day out, and like to keep in touch with my clients after our kitchen projects are completed, so receive lots of useful feedback. As a designer (as well as being a mum & wife) there are several points you raise which are eternal talking points when it comes to kitchen design.

Always go for a hob in the island, if at all possible from a services point of view, and ideally, go for a sleek, easy to clean induction which can double up as worktop when not in use, rather than a gas model. Sinks seem constantly to have water, splashes, and at least a few dirty mugs around them (despite our dishwashers) whereas hobs tend only to be in use once a day, so a hob is a much 'cleaner' option.

Don't let an extractor stop you from creating a feature with pendant lighting. With an integrated ceiling extractor over a hob, there is no reason to skip feature pendants to zone your island seating.

Think carefully about the position of your island seating - this seating will probably be the best used in the house! You have loads of space to have a fantastic deep island with seating opposite but far enough away from the hob, which will then allow a view of your garden out of those wide sliding glass doors.

Good luck, hope all goes well for you :-)