[LAD] LADSPA plugin behavior and naming, and more general questions

As a learning exercise, I made a LADSPA plugin that adds its inputs. I figured it would be reasonable to call such a thing '+'. Some plugin hosts don't like that (I was less surprised by the ones that could not handle the name '<'). This is the LADSPA_Descriptor.Label property. ladspa.h says "Labels must not contain white-space characters.". Is it unreasonable to expect to be able to have symbols as plugin labels, or parts of plugin labels? So this is more of a "what do you think" then a right/wrong answer kind of thing. Also, though ladspa.h does not say I cannot write my plugin library in such a way as to create resources shared by all the instances of my plugins within one host (say, a shared OSC connection?), would that be acceptable? Would that break hosts? What about per plugin GUI? If I just made a Makefile variable for a GUI to launch for a ladspa plugin, if I did not want the overhead of the full DSSI interface (or if I wanted to use the plugin in a non DSSI compatible host), would that be beyond the pale for a LADSPA plugin? Also, now that GMPI seems all but officially dead, does anyone think DSSI will be supplanted (or "disposed of", as its name would imply)? What is the general developer feeling regarding LADSPA/DSSI/LV2? I leave VST out of this list, because I don't think Linux distros can even legally distribute vst.h.