The photo below is my suggestion for colour of floor. Furniture should be darker - similar to below. For the rug - choose one colour from the artwork and find a similar coloured rug. Don't put a mantle over the fireplace - it could be a health hazard - bumps and bruises. Blinds - unless you want them to make a statement I think white - to match window frames would be fine.

Totally paint it! Really I like the tasteful matte black or white chalk paint with natural wood lid as you inspiration. But also what a fun opportunity to inject some colour: navy, mint, teal, yellow, orange can all work depending on the decor. ;-) You have inspired me! I am thinking to paint our chipped, ugly, red glossy piano too now. And I think it will get more use as a result too. Show us what you do!

Yes to much larger rug and accent cushions in var,hinge colours, sizes & textures. Love the white sheers, striking floor lamp and large plants in raised pot stands. I also would be inclined to swap out the existing coffee table and side tables for glass-topped ones, a large circular & gold for coffee table, and either round or square side tables. I'm guessing the furniture is angled to take advantage of the view? It isn't welcoming as is so I would experiment with different arrangements. Where does that small pocket door lead? What is the room right behind the living room (where large door opening is)?

Tiles will need a very stable base to avoid cracking if the house subtly moves. We’ve had a couple of very solid floor tiles break after minor impacts in our pre 1947 Qld home. Laid in the bathroom, to code, but still fine cracks in a couple of places. All doable on timber floor, but not as straight forward as laying on a concrete slab. (I love cork for all these reasons and it doesn’t have to be scarey orange anymore. Very flexible and durable but I know I’m firmly in the minority with that one!)