Redesign exterior stairs: from ugly colorful granite to...?

Hello everyone,

the outdoor stairs of our house are almost 25 years old, I think the previous owner wanted to handle this item quite cheaply back then. It is this brightly colored (is that the right word?) granite. In terms of the quality of the stone, the stairs are certainly still perfectly fine. To me, they are too bright, too restless; something darker, solid-colored would fit better with the house, the front door. Maybe this question / idea is totally nonsensical, but is there any possibility to redesign the existing stairs, to make them darker / solid-colored? Is it possible to apply some kind of coating over them? Painting is certainly the completely wrong word, but you know what I mean?

This is what she looks like;

And if anyone has a tip on which cleaning or scouring agent to use to really clean this type of stairs, to get rid of all the green growth, discolorations, would be greatly appreciated.

Cleaning with granite stone cleaner. The only long-lasting solution I see is to remove the old covering and install a new one. Painting/coating does not last. Simply laying a new covering on top may cause height issues without saving much effort.

Replacing the granite with dark tiles / stones is, in my opinion, a mistake. Then you will only be cleaning all the time, because on dark stones you see every tiny fluff, not to mention shoe prints. Besides, granite is a solid, real stone and not an artificial, fragile thing that you will have to repair in 2 years because it is broken. Of course, it’s all a matter of taste. But I would take a close look at the alternatives first before condemning the "old." Comparable quality is likely to cost quite a bit. A thorough cleaning should already do a lot for the appearance.

I had a concrete terrace slab completely stained brown with blossom dirt. Nothing would remove it, I scrubbed, tried stone cleaner, steam cleaner didn’t help either. Then I tried Lithofin outdoor cleaner again and that was pure magic! I rubbed the stone and rinsed it off after 4 hours, after that the stone looked like new. I can really recommend the cleaner. But I wouldn’t just replace such an expensive granite staircase.

Best regards
Sabine