I suspect some enterprising folks will write some standardized libraries. Quite a few people are working on compilers in various languages, including libraries and modifications for off the shelf compilers.
Whether you should expect language libraries from the CX16 team.. I kind of doubt it. Language support for compilers will come from the community.
Speaking of...I encourage people building graphics libraries, compilers, or compiler modifications to submit those to the Wiiki, so that these are available for other people to use.
You'd have to build the whole board, since the DAC and level shifters are physical hardware. However, i do not think the VHDL nor the schematics are publicly available, yet. The emulator is the best we have for software development and testing.
IIUC, Greg King (who has been working on the X16 support for cc65) has implementing a port of the Tiny Graphics Library on the spike, but I have no idea when they are likely to get to that.
I was planning on working at learning more assembly-based VERA programming this week, which would have hopefully resulted in a handful of useful routines, but I had a health problem which put me in the hospital for a number of days. I may start at it again as I recuperate, but I'll have to take it slow as I'll still need a lot of rest.