You can increase the font size which will make the boxes bigger. Also, you
might like the new inlet/outlet highlighting that's in Pd-extended 0.43 and pd-l2ork. The inlets and outlets are tagged using Tk tags, so you should be able to change their size using the Tk canvas commands 'coords' or 'itemconfigure -width', etc. I've never tried tho.
Their hitboxes aren't though - canvas_doclick in g_editor.c has hard-coded numbers.
Arg, yes, that's true... sigh... but I find the inlet/outlet highlighting helps a lot.
If I were to try make a patch, what do you think the appropriate place to expose it? It feels like it would sit well beside the font size options...