The problem is that for those applications, while you can do them with a mobile app, for professional grade work, a desktop is still going to be used. First the amount of power available is significantly higher.
Second, many of those tasks require a larger screen. Even a rumored 12" iPad screen isn't going to be enough for serious professionals. Start adding in tool bars and other necessary information and that 12" disappears in a hurry.
As much as you might want to be able to do all of those things, there isn't enough of a market to justify the existence of such a product. There aren't enough people like you yet to justify the product on a massive scale and in trying to satisfy the requirements or demands of a niche group of users, you invariably end up with something like this: