Thanks, some very helpful information in that link discussion.
The bit about number of keys rather than size was helpful as well. I am testing a solution for compression of core data into character separated strings and then dynamically 'unpacking' that on addon load. Which should be relatively quick using zo_strgmatch(tString, "%S+") type of step process.
According to wiki
Lua can process text strings in excess of 230,000 characters so this should be more than adequate for any conceivable use scenario.