This is a great thread and I fully agree. One other element I would add would be PRACTICE. Yes that dreaded word again. Practice will improve all the other elements that were posted at the beginning of this thread. The better your slights are for a trick, the more you can focus on presentation...
Ive been in magic for about a year and a half, but am new to Theory 11. I thought I should introduce myself and I look forward to meeting, talking, and growing as a magician and performer with you guys.
Have a good one.