I would stick with one story because an accident, disability or aging would make a two story less accessible.

Ditto! Lol. Carpet is much quieter and safer (I've slid down my previous 'all wooden' steps before now!) but I hate it too. If you have good treads, I'd go for a stylish runner which looks nicer. Get a busy pattern ie stripes or funky geometries to keep the dirt less obvious.

cover the tiles with something thin such as Amtico

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