Code highlighting is helpful - I presume that would be a minimum.
Preview is nice to have but doesnt seem to be essential - I especially like where I press a hotkey to show preview and same key to toggle back to code. I cant remember which editor had that - I think it was the one I liked least otherwise :-(
I'm surprised by the other editors that allow preview on a different tab but dont give you any hotkey to get there...
Code completion is nice
thinking of Shade's point that to do it all manually is a good way to learn...
It is nice to think that one can learn everything, but if something is seldom used, I think having a button/menu-entry that does the job is not a bad thing.
Using a button or shortcut for most tags seems reasonable/helpful to me. Learning what things like
float:right and
clear:both mean and how they're used - that can neither be helped nor hindered by a button.
One thing I didnt mention before is I want to be able to write in German (on the resulting website) i.e. include in particular:
ö ä ü ß
I was told to use UTF-8 encoding and then simply use the characters directly as they are - I see some editors show them as special characters, some not.
Otherwise, as a beginner, I'm not really sure what I need
(currently downloading Sublime Text - thanks wraith)