A single bright ceiling light makes a small room look like a small room. Layered light makes the same volume read as several places.
Ambient light should be indirect
A downlight grid in a compact ceiling flattens everything and puts your own shadow on whatever you are doing. Light bounced off the ceiling or a wall gives the same illumination without the flatness and without the glare from a loft bed.
A cove or an uplight above the kitchen run is the usual answer. It costs a channel detail on the drawing and nothing afterwards.
Task light where the tasks are
Under-cabinet light on the worktop, a directional light at the desk, a reading light each side of the bed. Each is small, each is switched separately, and together they let you light one part of the house without lighting all of it.
That selectivity is what makes a compact interior feel larger after dark: a lit corner and a dim one read as two spaces.
Accent light does the rest
One fitting picking out a texture — the cladding on a feature wall, a shelf, a plant — gives the eye somewhere to go. In a small room that is disproportionately effective and costs one circuit.
Outside, a single light on the terrace tree or the facade extends the visual space beyond the glass. At night an unlit window is a black mirror; a lit exterior gives you back the view.
Colour temperature and dimming
Warm white, around 2700K, everywhere you relax; neutral, around 3500K, over the worktop and the desk. Mixing them within one sightline looks like a mistake, so decide the boundary on the plan.
Dim everything you can. In a small volume the difference between full and quarter output is the difference between a kitchen and a living room.
Wiring it is a production decision
Every circuit, switch position and driver location is fixed when the walls close. Adding a two-way switch at the loft, or a socket for a floor lamp where the sofa will be, is a line on a drawing now and a chase in a finished wall later.
Mark the furniture on the plan before the lighting is set out. Lighting designed against an empty plan lands in the wrong places.