I know what you mean about all the different choices for axes. I think the most sensible bet it to keep them as temperature in Kelvin, and density in m^-3 – ie. SI units. Combining the energy confinement time into the density axis (Lawson parameter) means highlighting any areas is specific to a particular reaction ie D-T.
For a fancier animated version you could include the confinement time as a third axis – so make it a 3D cube you are flying through.
Also alongside each axis you could have other reference points such as the density of water.
Style-wise I was looking recently at some of the xkcd posters such as http://xkcd.com/681/ or http://xkcd.com/482/ where the large scales of the universe are explained with ease (and a little humor) Maybe we could get him on-board to do a fusion poster and post it on xkcd – that would generate some publicity!
If you want to see how a magnet bends a plasma, watch this: http://www.youtube.com/watch?v=3grPo81fBrA The mugs were available from thinkgeek.com but I can’t see them on their site right now