Thanks all for your very helpful insight. I think you talked me off the ledge of trying to go iPad only and use it as the sole device. I think my desires of having a machine that can edit photos, manage iTunes, create docs and store tons of stuff makes it pretty much a no brainer to go with a Macbook or iMac.
So, what i'm going to do is try to find a used Macbook AND iPad. going new might set me back $2000. Going used i could probably get a model version older on both and save 50%.
Thanks for your help everyone!