I would not choose a granite-Silestone unless I could see the stone with the cabinets. Bring home stone samples or if that is not allowed, take a kitchen cabinet drawer with you to make sure the stone color is a good choice. It is always best to block the sun before it hits the glass, if possible. See photo.

I think you're right to change your plans tbh, I think pic 1 and 3 would work. Another option is a suspended woodburner. It's obviously not a divide but it gives you the break in the ceiling so acts as one. The first one attached is from fireplaceproductsUK. The other 2 are just images from leotrippi and homedesignht to show how they can act to divide a room. A much more expensive option is a glass fireplace, this is from acucraft fireplaces. I'm not sure how easy it is to find UK manufacturers/suppliers though. Alternatively you can just break the room with furniture layout and ceiling lights. The lights if hung properly ie at differing heights, clusters etc along with floor lamps will stop that cavernous feel. I can't obviously see the plan but if you're really set on a divide, and they are great!, you could set it off a side wall rather than down the centre of the room.

I come to the part of my build were I have to make a decision on how to heat it ! So far my spec for insulation in my 2200 sq ft house is .. A larger 150 mm cavity with higher amount of insulation (not sure I think 130mm), walls are going to be dry lined and extra insulation is going into the attic. The Windows are going be tribal glazed with the higher spec of insulation. Under floor heating upstairs and down. Now I've to make a decision on how to heat it !! Have I enough insulation that an oil boiler would be fine or should I go for geothermal or air to heat ? I don't have room for a wood chip burner even though they have become more compact.. I've heard such horror story's of electric bills with the "air to heat" but my house isn't to massive. If anyone has had any experience with these systems can you tell me about them. I did go to a building show and they all sound brilliant but the they are all trying to sell a product! Thank you

We are in the process of renovating our kitchen, including knocking through into the dining room and adding french doors from the dining room to the garden. It's west facing and doesn't get huge amounts of sunlight. I'm trying to figure out what to do about lighting. We have 3 pendants that will go over the peninsula but otherwise no lighting decisions - although as we are redoing the ceiling, recessed spots seem like a good idea. The kitchen cabinets will be pale grey high gloss, with an oak worktop. Other than the oven cabinet and the freezer/fridge/pantry wall, there are no high cabinets. My main issues are: where to place spots centre light in dining area: we tend to move the table depending on season/events/mood so don't necessarily want to be stuck with a pendant light that only works best directly above the table do I need spots interspersed with the pendants over the peninsula (they are heavy ceramic so will likely not cast much ambient light). It will be my main baking/food prep area so light will be important. (General plan of kitchen - not entirely to scale but gives a good idea of plans. About 30 sq m in total - the long wall with window and french doors is about 7 m)