What I have is already my ideal setup:
14, 27, 56
14 - classic wide angle of view, without introducing extreme distortion. Makes viewer feel like you're in the scene.
27 - perfect normal field of view (focal length == sensor diagonal), very compact, super-sharp. Unlike 23 that I often found a tad too wide, or 35 that I found a bit too narrow. Images feel very natural.
56 - classic portrait perspective, shallow depth of field. Great for focussing on details and removing all distractions
Seldom commented on observation: field of view covered by each of these lenses is almost exactly half the previous one. i.e. 27 is almost exactly half as wide as 14, and 56 is almost exactly half as wide at 27, making it easy to visualize what you'll get by switching from one lens to another in this setup.