Hello Ernesto,
There are a number of efforts underway to provide better data vis libraries for haskell. Likewise, there was some recent discussion on the Diagrams mailing list about data vis tooling, and there should be a few interesting tools surfacing over the coming few months.
My immediate concern is that this project is too broad and undefined in scope to be a successful Haskell GSOC.
A successful GSOC project should have
a) a clear notion of what project's goal is
b) clear evidence that the planned work can reasonably be done over the summer
c) the result of a successful project would be valuable to the general haskell community
It sounds like the core of what you want to do is write a small lib that transforms a data set from some initial "schema" into the "schema" thats suitable for some underlying choice in plotting tool. This is a useful thing to do, but not large enough in scope for a GSOC project.
On the flip side, interactive data vis tools are *hard* to do well, and a GSOC that proposed to work on that from scratch would be very very risky unless you've spent a lot of time working on building such tools.
You're definitely pointing at region of library space where more nice tools for haskell would be very valuable, and which a number of folks are trying to address. But, for GSOC, unless its a very very clearly laid out proposal, it will be deemed too risky.
I warmly recommend you look at prior years' Haskell GSOC projects to get a feel for what strong successful projects/proposals look like.
cheers
-Carter