If you do hardwood, which I think will be beautiful, use a runner.

Not a pro but when we asked about doing something similar we were told we'd have to basically rebuild the stairs. It wasn't going to be cheap. If you are OK with that cost, then it's more of a personal preference. If you wear socks in your house, hardwood stairs will need something to grip so you don't slip. YOu might end up putting a runner on it anyway - so then it's just an expensive way to put carpet back on your stairs. If your upstairs is carpet, I would just replace carpet.

Our neighbors just replaced all of the flooring in their entire house to hardwood, except left both sets of stairs carpet due to the cost.

I would do the best of both worlds - hardwood with a runner. What is currently underneath the carpet? Original hardwood? I think installing all new wood is going to be like having the stairs rebuilt. If that is the case then either refinish original hardwood, or rip up the carpet, paint the stairs white and install a runner down the middle.

The floors you have appear to be Brazilian Cherry. If you could at least stain the treads to match what you have, that would be preferable. It may not be easy and require some testing--If you have decent treads under there to start.

And then I would do a runner.

We took the carpet off our steps and considered refinishing them, except they aren't very nice. I nearly broke my collarbone on the bare steps after falling head first down the stairs, so I am biased: we are recarpeting.

I think new treads are going to be amust so think hard about the hardwood floor you are thinking of for the rest of the house ( I am assuming repurpose means change) I think you could do a runner it looks like your decor is traditional so arunner would be appropriate

I had carpeted stairs. A few years ago we had a new oak staircase installed by a wonderful and talented carpenter who specialized in staircases. He worked alone; no helpers! He even matched the staircase stain to our Italian porcelain wood look tile flooring. We are quite happy with the outcome. I love oak staircases! Best of luck on your journey.

I had a similar situation but the stairs were made of particle board. I wanted to use oak treads but that would change all the height measurements and be hard to fasten securely to the particle board. There was not enough room in the house to rebuild the stairs to current code using new treads. I think now you need 10” riser to riser with 36” landings. So I could not do oak treads. There may have been some kind of cladding option with other flooring. I was not interested in that, since I was trying to match a solid hardwood floor.

It appears some of your treads are painted white. What is the material underneath? If it’s solid wood, what would happen if you stripped the paint? You should know the construction of your current stairs before making decisions. Sometimes you can get underneath them in a closet or crawl space to see what is going on. Maybe the treads are already solid wood that you could strip and stain.

Regardless, a rug runner will make them safer. Your side stringers are not carpeted, so it’s kind of like you have a wide runner anyway. You could opt for a thinner carpet to make it more like a runner, however if it is not cut pile it is likely that staples would show or it may have to be glued. Ask your carpet supplier what the options are. I think it looks nice with carpet and is not worth doing hardwood unless hardwood is already there.