Hi there, I think that the skylight would definitely be the way to go, if your budget runs to it. It will really lift the whole stairwell and make it much lighter and brighter. Full height frosted doors may be OK on the laundry, but I wouldn't recommend it for the bathroom as when lights are on in the room, you may be able to see more than you bargained for, from the corridor. The occupants of the house may feel comfortable with it, but any guests or visitors may not. A frosted panel at the top of the door would be as far as I'd go. Bear in mind too, that glass lets more sound through than timber, and in a situation like yours, I'd recommend a solid core door, for that reason. I hope this helps!

I’d also go clear, for the same reason as Kate. You could always add frosting appliqué, an easy and inexpensive diy that doesn’t look like an add on, should it not suit. I’m surprised tho to find a solid Tas Oak / Vic Ash door is more expensive than a double glazed glass door - not questioning you, just genuinely surprised

I think you should add a skylight, even if you pay a fortune to retrofit glass in the door it won’t make much difference because you still need to maintain enough timber in the door for security. I had the same problem in my 50Ish house . I installed one skylight close to the door and one further down the corridor, all done in few hours and looks great.

Tinting the sidelites to match your black entrance door is a fantastic idea for privacy and style. Here are some thoughts:A graphite tint could indeed look sleek and complement the black door beautifully. It'll give your entrance a cohesive, modern look.Whether to tint before or after installation might depend on the specific installation process, but doing it before could save you from extra hassle. Definitely worth checking with a professional.For more insights and ideas, you might want to explore https://www.enerco.co.uk . They might have some valuable tips on door enhancements and styling.