I have just uploaded a new version of LaTeX-Encode. This vastly increases the number of Unicode characters that are recognized (but still only about 350 characters). Two new functions are included: add_latex_encodings() and remove_latex_encodings() to change the encoding table, plus reset_latex_encodings() to reset back to the original table.
The encoding table is built by the script "build-character-table", which has rules for building latin accented characters, grabbing encodings from Pod::LaTeX, and a set of explicit encodings. Patches to extend this script, and thereby increase the coverage of the Unicode character repetoire, would be welcome, as would any other feedback.