Haven’t been to Oviedo, per se, but around the coast up there.
Tends to rain a good bit but the whole are is amazingly beautiful. The whole Asturias, Galician area is for sure some of my favorite landscape in the world. You are also close to Bilbao which is an amazing medium sized city with spots on end, hills, stairs, culture and is cheap as can be.
Bring some painting/drawing stuff or a guitar/whatever for rainy days and you’ll have the best time never wanting to leave