Why not keep your front door as is (paint with another colour if you wish) and if the budget allows, add wrought iron gates over the existing doors in a glossy dark grey (black maybe?) This would pick up on the wrought iron you already have at the top of the steps. You could also maybe think bout adding glass panels to your doors?

You can get an electric hoist for your light. We have a 1.8 meter high chandelier in our front entry. It has an electric hoist mounted in the roof, that is rated to 100kg, and comes with it's own remote control

Definitely requires wallpaper or paint. I would probably go a textured wallpaper like a bronze /gold weave wall paper. It will give the area deapth and frame the space to make a statement. You have the furniture and space for it. Large art or a mirror. I would possibly keep it rectangular or squarish. A rug would soften and fill the space but would have to be selected carefully to ensure no tripping hazard. Maybe something patterned (replicated through abstract & lines like the legs of your table, with a pop of colour and upgrade the vase of flowers to reflect this colour. Basis of design is replication whether it is colour, shape or pattern.

1 -- leave the existing lights , or maybe go bigger but in a similar style . I like those string ball ones -- you could possibly even have some fun and go for a bold colour , depending on the rest of your house . 2 -- wallpaper the feature wall in an 'interesting' burgundy or even reddish/pink pattern , maybe some scrolls or maybe with a fine gold stripe embedded . 3 -- if you want to stay white or any of the 19472 variations through to beige , add a large colourful abstract painting -- at least 1.5metres x 1.2 . 4 -- that 'roof step' where 1 of the lights is looks out of place -- I'd paint the 2 sides in a charcoal/real deep steel blue ( darker than the carpet but still showing some homage to it ) . I doubt it would darken the stairwell too much , but it would look more balanced and cohesive . The bricks are 'interesting' and doing anything with them could be tacky IMO , the stairs and floors are fine as you have worked out , it just needs a feature wall or focus .