I bought and returned the 1.3. Why? Yes, I agree with you that the MB can perform the tasks you mentioned above. But there is A CATCH. You can't do all these tasks at once. The MB is very poor in multitasking. In personal tests, the 1.3 MB is hyper lag and slow during my stress tests, where I ran Parallel Win 7 (with Excel + Word running) + Keynote + Safari + iTunes + Photoshop + Statistical software simultaneously.
My 2013 MBA performs these tasks without a single glitch. If you just run one app at a time, there is no significant different in performance between MB and MBA. For example, with a mere 1-2 background apps running, MB and MBA take the same amount of time to execute a photoshop task. However, when there are heaps of background apps, the MB struggles to catch up with MBA's superior performance.
I am not remorse as I can return it to Apple. I am just disappointed that the MB, to me, is an underpowered machine that suits for very basic single task oriented computing. As much as I love MB's superior screen and sexy footprint, I have to let it go. Meet the MB again in V2 or V3.
My verdict: Get the MB if you don't need to do extreme multitasking computing.