If what counts is that they're well rounded why do they give you the ability to customize to be less rounded, ie, 17" Inch MBP which is supposed to be a workstation replacement?

Out of what you mentioned: Tough, decent battery life, good performance, thin and light, decent screen size and resolution and graphics card, nice keyboard, in one package.

A t400 does the same, it's arguably as tough as a MBP, it's got better battery life (compare 10.5 hours vs Apple's advertised 7), the t400 is already thin and light, but the t400s takes it a bit further(albiet costing battery), screen size and resolution is the same even with LED, and switchable graphics are on all high-end laptops. Keyboard just depends on what you like anyway. Not to mention, with a Mac your portability and serviceability for your machine is greatly affected, ie, I can hibernate most modern PC's and change the battery while you can't. I can replace the battery when it dies and you can't without voiding warranty. You can't replace ram, keyboard, or anything without Apple service or risking a void warranty.