That shade of red is not the best, indeed; you could find a darker one, if you still want red. However, personally, I'd go with black. You can do the metal frame in the same paint or choose a glossy one for a bit of contrast. You could also paint the inside - either in black, so it's all the same or in white, to match the rest of the room. Some chose to do the bricks in white and the inside in black: Grey can work too: Or maybe green... Good luck!

I would first decide what style of interiors you like. I think your ceiling has artex. I would go right back to basics and get that plastered over so it is smooth. You obviously like a very clean line modern look and the artes is not in line with that. I also think some natural wood like oak would lift it. An oak bookcase, shelves or a low sideboard and a couple of side tables. I would look for a more natural dining table too. Everything is very hard edge. I would be tempted to paint one wall a greige or taupe shade and see if you like it. It needs some natural texture. Your finishes are all sharp edges and very modern materials. Think about adding some rattan accessories or a few curves. Some softness would make it more inviting.

First we need a floorplan. I'm not sure this is in the UK? Could you supply more information please such as furniture requirements, purpose of room and how many people would be using it?

Small changes and addition to your house will do the work because it is not an ugly house. Adding things: 1/ The proposed porch canopy for the entrance door and garden door are very positive ideas, I will add to it a barbecue grill porch attached to the house or free standing one just in front of the kitchen to garden door. 2/ a/ Changes : do not make great change on the facade of the house, because the stone covering is really nice, you can accentuate the stones by painting with mid brown the joints. My advice is to try different colours in very small portion to make your choice and then do it overall the building. b/ I really liked a lot the entrance door it is like the 70`s. But yeah you should change, 70`s is quite dark for 21 century. Change the door to dark blue, black, or yellow to accentuate the change. But you should think about the harmony with the things in the entrance, if you ever choose a blue door, place a blue postbox at the entrance. If you install blue window frames, place a a thcick woodwork mid brown coloured, park bench kind of thing in the garden. Brown is an universal colour, so Wood is the harmoniser in every part of the home. Note: some interior designer advice is to cover up the stone or the wood. I personally never liked covering something natural with unnatural things. I prefer the nature taking control on my view. I prefer the nature friendly homes. Your home can be like this. "In my opinion, there is never an ugly house, but a house that a talented architect didn`t touched it yet." My personal quote Oruc Kenan Yildirim. (Maybe Frank Lloyd Write said it and I was impressed by it, but forgot where did I read it). Oh and a last detail, as I am a pottery maker too, I loved the earthenware tiles on the entrance, it made me remember somehow French and Italian homes. Earthenware tiles are my child time love. I have weakness toward them. Let a talented architect just touch this home. You will see him/her making marvels from anything.