Hi,
Some of your ideas already reside in other projects, so perhaps consider
contributing to them rather than starting yet another project. IMHO what
we really need now in Linux community is a couple of really stable and
versatile apps, rather than a huge number of unfinished projects.
If you are interested in live-control of various audio/midi processes,
you may want to look into my RTMix. The latest version (that will be
available for download very shortly -- squashing last batch of the nasty
bugs :-) has midi and OSC implemented and can pose as a Midi
router/server as well as network host/client, as well as do various
algorhythmic things. What it does not have is sequencing capabilities
(other than routing the sequenced data), although it could be easily
expanded to accommodate for that functionality as well. I am sure there
are other similar projects out there that address your needs in one way
or the other.
For RTMix go here:
http://meowing.ccm.uc.edu/~ico/
Ico