I'm not sure to understand what you mean by a "mbrola-voices package", and in particular, "mbrola package has already a suggestion for this package on Karmic, even though this package still needs to be created.": mbrola suggests mbrola-voice (provided by all mbrola voice packages), not mbrola-voices. Would mrbola-voices just be a meta-package which depends on all the voices available in Ubuntu? Since that would result in installing several hundreds of Megabytes, I'm not sure it would really be useful to have.
I'm not sure to understand what you mean by a "mbrola-voices package", and in particular, "mbrola package has already a suggestion for this package on Karmic, even though this package still needs to be created.": mbrola suggests mbrola-voice (provided by all mbrola voice packages), not mbrola-voices. Would mrbola-voices just be a meta-package which depends on all the voices available in Ubuntu? Since that would result in installing several hundreds of Megabytes, I'm not sure it would really be useful to have.