Using the exponent function from 0 shouldn't cause any issues that I know of. If you apply a feather value to the selection, however, it has the potential to leave some rougher edges/elevations along the coast which isn't really a bad thing (think of the coastal regions of Norway, Sweden and the western coast of North America where a number of cliff like areas go right up to the waterline). I should mention that using the basin fill isn't a bad thing at all. I just tend to follow it up with some noise and precipitation to smooth out the transition from mountains to flatlands.
As far as getting rid of those bumps, I'm not sure what to suggest on that one. If waldronate happens along this thread, he might have a suggestion given his knowledge of both applications. For my part, ever since I installed the latest patch (li18hy0) for FTPro, I've not been able to import .mdr files back into FTPro without some serious issues.