My favourite paint company, by far, has to be The Little Greene Paint Company. Their paints contain up to 40% more pigment which means a deeper, longer lasting result.
What I love most about this company is the extensive variation of colour that they offer. Their colour scale range is a soft palette of colours which offers subtle variations in hue. Making it extremely easy to co-ordinate woodwork with the walls.
I've included below a few of my favourite colours and pictures that they feature on their website.