I would HIGHLY recommend a more traditional build than this for your first. Your first design will cost almost double what it would had you had some experience, and that is just building a normal Reprap. Trying to design it yourself at the same time as something original is likely going to double the price again, if not more.
It's very easy to get in over your head just building an already proven design and the changes you need to firmware and slicing would only make that even more likely. I'm not saying you can't do it, or it can't be done, just that for this to have any chance of succeeding at a reasonable price in the (semi) near future, start with a smaller mountain to climb and get some experience first. You aren't just diving in, you're heading straight up to the high dive.
It's very easy to get in over your head just building an already proven design and the changes you need to firmware and slicing would only make that even more likely. I'm not saying you can't do it, or it can't be done, just that for this to have any chance of succeeding at a reasonable price in the (semi) near future, start with a smaller mountain to climb and get some experience first. You aren't just diving in, you're heading straight up to the high dive.