I think we can put in another way.
For me is a nonsense to talk about display size, because it can be a 4.3" but with a big bezel. ONE S has a bigger bezel for example (just go and read the dimensions, you'll see more mm than sensation). So the important thing is the overall dimension.
I think that the perfect phone has a 720p rgb full display (4.3, or 4.5 with no bezel I don't care), with a removable long lasting battery and with dimensions smaller than 64*125.
HTC Sensation Z710e- ViperS 3.1.4
Samsung Galaxy Tab 8.9 GT-P7310 - StockRom V8