Ed, I’d assumed that your spoke-shave was reasonably well-fettled, but Larry Gelb has a point when he mentions the importance of secure seating for the blade and cap-iron….. it’s best to get this part right.
By all means use rasps and other shaping tools if you wish, but you’ll still need to clean up the surfaces. As far as shaping with a well-set scraper is concerned – i.e. one that has a generous hook to remove thicker shavings – if the band-saw marks are not too well defined I would expect a scraper to be able to deal with it, first removing the saw marks, then evening the surface, finally graduating to a less harsh setting with finer scrapers when you near completion.
I keep mentioning the Stanley 82 scraper because this is what i would use for that initial task because it can lend itself to curved work on the flat.
I don’t make rockers often, but when I do, typically the rockers are roughed from the basic stock and when I have a pair, I ensure that the curves are equal in shape by gluing them together, side by side with diluted glue and a sheet of newspaper in between. This gives them enough strength to allow what I’m going to do but also lets me break the joint later, then clean it up. I use the same technique with curved chair backs, too, to ensure an exact pair.
I can then do all the shaping on both rocker (or leg) pieces, using what ever tools I need, but typically a heavy-set scraper, to get the shape and surface right, then cleaning everything up with lighter scrapers to the point where they can be separated and finished individually.
That’s my method, anyway. No doubt others do it differently.
You can extend the same method to other curved sections if it suits.