I'm more amazed by how powerful Word apparently is than by the overly simplistic iOS7 design. It seems to have much more features than your standard Paint, being more related to GIMP than the former.
I think you can do any design with any program if you have the skills. I have used the technique of using a custom shape to cover up things. I didn't know that was possible in Word until I was skilled in Photoshop and Illustrator. Design softwares don't differ in the features themselves, they differ in the accessibility of the features. Gimp, Illustrator, Correll, Word all the same basic things: shapes, text, colors, gradients. The advantages of higher end softwares are you move things around easily, work with vectors, work with bitmaps, have easily accessible layers, hide things, print certain layers, make sure it's pixel perfect, clone stamp etc.
The same is true of Excel. That program is obscenely powerful with what it can do. But of course, 98% of the people that use it will never know or care since they don't need anything more than a basic core set of features that are present on most other spreadsheet programs as well.