still confused with TTS Please help!

[krishnakant Mane]

hello all,
I have been asking this question for quite some time.  May be I have
been stupid enough to understand it right.  but probably I feel that
the point may not have been understood by all my friends on this list.
 I infact asked the question time and again.  so here it is in as
simple words as possible.
I want to use festival or flite on my device.  it is a single board
computer with an intel chipset and 128 mb ram.  the board has AC 97
sound card.
I want to know that if I will like to create new voices, with festvox
for festival,  can I improve the quality of speach?  I mean if I
develop new voices, will I still be getting the existing quality of
diphone or other voices on the festvox site demo?  or can I develop my
own voices with better quality.  in short just tell me is it possible
to develop voices as good as dectalk with festival and festvox
provided we have all the resources?
if that is possible then I will like to contrubute new voices with
better inflection and tone.
secondly I am deciding to develop a few voices in Hindi and other
indian languages.
thanks,
Krishnakant.