Grey will look dark with the brown floors.Beige is a good option but I think you should go for white walls. Simply white BM is best for this space.

This is simply white BM on walls with almost the same floor

I also did a beige toned combination for you to have an idea how it looks

The hallway badly needs a rug.This blog will be very helpful If you thought of purchasing a rug.

Which runners to choose for hallway?

You can go with silver/gray, just need to get better light.

Darker

BM Manchester tan. It is a popular beige color and looks good in any light.

Inhave used it in three different situations, all without fail.

Ivory.

If you like it, try Grecian Ivory SW.