Shakespeare's Scansion: the Sequel

Is there a rule or pattern that would enable to create two lists of words: the first consisting of words that can be shortened through elision; the second of words that can't ?

I don't think so because it's not a question of rule nor pattern nor decree but of current use. So if this list could proceed from observation, it shall admit exception. I doubt one could proclaim a prescription...

Metrical treatment of secondarily stressed, and weak, syllables varies among authors a great deal, and it is a matter of stylistics as much as it is of the synchronic state of the language. Shakespeare has much less elision than, say, John Donne whose contractions were extreme by comparison (and quite possibly reflected a different style of speaking.)

curious is indeed given metrically disyllabic variants in Shakespeare, in lines like the following

Hung by a curious Bauldricke, when he frownes

I am so fraught with curious business that

This is too curious-good, this blunt and ill:

If my slight muse do please these curious days,

In a most curious mantle, wrought by th' hand