I've been thinking about using the same transformation commands/methods for 2D and 3D. In the end, I still have some getting-used-to's in the pipeline that are all about matrices and vectors, so it's probably the best to tinker with it more than just to get the job done. After all, writing GLSL seems to simple in the end that the only thing you need to know is the maths behind. I mean I had all this stuff in the previous semesters, so it's probably no hurdle to add some macros dealing with all important matrix stuff, having some premade matrix operations and so on.
However, the idea of just having the same command set for 2D and 3D simply pleases my inner n-dimensionalizer. I'm having quite a bunch of interesting ideas to easily build all sorts of nice effects with a few fixed data structs to pass. The more I think about the possibilities, the less I tend to rethink it. That's a good thing because it enables stuff to move forward as well as giving me the instant success I need right now.