If you're not currently backing up your data on your macbook, get the time capsule. (At least I would.)
As far as the iPad 2 is concerned, you should consider whether it fills a "niche" between your laptop and your phone. I've found, for example, that I cannot possibly use my iPad as an adequate substitute for my laptop (or my desktop.) On the other hand, my highly capable smartphone is now reduced to (a) making phone calls and (b) providing vocal GPS directions when I drive. Otherwise, it sits unused.
But that's me. Others, I think, have a completely different experience. Their laptops are overkill for their work/entertainment requirements and if it were not for the need to sync their iPads, they wouldn't need a laptop. And some find that compared to their iPhones the iPad is too heavy, too big, and can't be put in a pocket.
In short, the iPad is a niche player. How wide that niche is and how much overlap exists with other gadgets depends on how you use each.