BareMetal:
Q1 which / where is the best, most complete, most up2date package that includes the majority of the above?
Probably Tom Carpenter's fork...
Q2 my current setup includes only 8 and 14pin variants, I want to start adding 20pin 2313/4313. in the absence of a total solution to Q1, same question for a tiny20 variants bolt-on?
Probably Tom Carpenter's fork.
Q3 I cant seem to find the latest documentation for ALL options and range of possible values in boards.txt, programmers.txt. for example I have recently discovered protocol=arduino where previously id seen protocol=stk500v2 or suchlike...whats the difference/advantage/new features etc?
For which IDE?
if I have to add my own for rare cpus, im ready to do that, but id like the best possible starting point.
Well, if you're very patient, I would certainly welcome another participant for Tiny Core 2.