Flooring - in a similar situation I used a thick-ish laminate, they vary from about 8mm to 11 or 12, over a decent thick underlay and its been fine for 8 years. I chose a laminate with quite wide long panels which meant a bit more cutting but maybe a bit more stability when it was down. I prefer to take skirtings off, lay to within 10mm of wall (for expansion) then put skirtings back on top.
Kitchen - no experience of anything other than the one I fitted, IKEA. Again doing fine after 8 years in a proper hard-worked kitchen. IKEA is all flat pack which has + and -. The - is you have to put it together, the + is you can do it in batches and install so you don't run out of space. One feature is the lack of a gap twixt wall and unit back. That gives you about 15-20% more internal room in cupboards and particularly drawers which are very space efficient, but it can make more work. For instance the sink plumbing ran horizontally at knee height behind 4 cabinets in the old kitchen, in the new one I had to make up a new set and bring it all down to ankle height to run below the cupboard bottoms. I have heard good things about Howdens as well.
Appliances - I've done pretty well with Bosch, sometimes you get good prices on 'last years model' from people like AO. They don't call it that but its pretty obvious that there is a £XXX one and a £XX one with similar spec. Worth a search on their, and others, website. Having spent ages wrestling with replacing fully fitted/mock door stuff in a house my sister in law bought - dishwasher leaky, Fridge door cracked and if you turned the freezer on the whole kitchen circuit MCB tripped out - I resolved to have freestanding standard size appliance - a 60cm white dishwasher sits under the work surface, if it packs up I drag it out and push a new one in. You will always be able to buy a 60cm one at a decent price unlike odd sizes. Same with fridge and freezer, they free stand along one wall.
Generally - lots of suppliers/retailers are under financial and rent pressure right now and I wouldn't be surprised if a few folded or went into pre-pack administration which of course leaves customers who have pre-paid for orders losing their money. Pay by credit card - at least you get some protection if that happens. (OK, I'm a pessimist).