Many thanks for the tips and insights. It'll take a while to churn it all over.
In the meantime I'll go with the long varchar, especially if I can word wrap in a grid (which is altogether another question). Varchar has some distinct advantages over Text, and apparently only uses memory for the length of the contents, not the size of the field, except for in-memory tables. So I can probably work around that. My database is single-user, standalone, and unlikely ever to take more than about 100K records, so maybe I can afford to be a bit more resource intensive anyway.