Ideally you could do with a kitchen retailer with their own builder. Perhaps someone can recommend someone depending on where you live. Personally I would be considering taking out the window and having French doors here. Then you would have a run of units on the two remaining walls and a bigger island in the middle

Your photo has appeared since I posted. Yes, to the mirrored pillar. Maybe your choice is dependent upon your room styles. Mirrored would suit contemporary and shelves a more traditional look.

I certainly agree with the comment about making the utility room door open outwards. We had a decent sized, but fairly narrow, bathroom to renovate. The door was about halfway down the long side and making the door open outwards made all the difference. So far as your supporting pole is concerned, this might be of interest - take a look at the final photo where the pillar has been boxed in with mirrors. It could be a stylish solution, unless your kitchen is a Farmhouse style or similar of course! https://www.houzz.co.uk/magazine/how-to-work-around-a-structural-pillar-in-your-kitchen-extension-stsetivw-vs~76437319

Hi, you can't just apply a £2k/m2 rate, particularly with small jobs like this. The extra depth may not necessarially increase proportionately at the average rate if you keep within the span limits of the floor and roof elements (ie don't need a lot more additional foundations or structure, for example). Also, it may not be as simple as 'getting a box frame steel in place'. Big steels have big loads that of course only go down at the ends - your existing walls may not be able to take these higher loads so you can end up having to re-build these parts and/or make new foundations to take it. This can all be time consuming, disruptive and complicated to install so the extra costs aren't just in the 'bit of steel'. If you have a builder in mind an early discussion about 2 options might help inform this. My point is that you need to consider the detail and therefore likely costs and consequences of what the engineering will be so that you can make a valued judgement on whether it is worth it or not. You might well come back to the steel being the right answer but at least then you'll know that.