I really liked Zim many years ago and used it quite a bit for personal note taking, but its lack of tables really annoyed me. I love tables with a passion.

(On that note: when you add table support to a markup language PLEASE support newlines and paragraphs inside table cells. Don't assume that all tables are spreadsheets with only a small amount of text per cell. Some of us live in tables like high-rise apartments, eg bug tracking, school note taking & image stacking in cells.)