I can't seem to get the YTICKFORMAT parameter to PLOT to have any effect. It also will not accept an array, although that is also an acceptable value in IDL (according to docs).
Problem: When plotting yrange -0.05 to 0.05, GDL forces yticks to scientific notation and puts '(x10-2)' above the y-axis. This is unacceptable to some and I cannot find a way to avoid it in GDL. Perhaps there is a way to disable scientific notation for ticks?
Please have a look at the last cvs version, many of the annoying differences you cite have i believe, disappeared. (Although tickformat support is not 100% complete yet).