if youre in fitzrovia, russell and hodge are quite close by. pied a terre for dining on charlotte st as well. charlotte st has lots of nice dining options.
marylebone high st might be a bit of a walk across, bit if you make it to the fromagerie, pop in next door to the ginger pig and get a sausage roll as well. then maybe downstairs at matches on the high st. then walk south and go down st christopher's place, then on to selfridges