A fault of modern source editors?

A lot of your points have merit, but one thing you mentioned is less 
useful than it might at first appear: the `code template' stuff, where you 
type 'for ' and the editor types in (;;) and sticks you after the opening 
bracket. This is problematical for several reasons:

Firstly, the editor is making your cursor jump around without your having 
commanded it to move, and both the point it left and the place it moved to 
is essentially arbitrary (does your editor's template matcher fire after 
space? Bracket? Which section of the for does it move you to? Perhaps it 
moves you to the loop body...)

Secondly, once you're there, there's no way the editor can automatically 
tell that you've finished typing in one section and want to move to the 
next, so you'll have to tell it. Had the template not been there, you 
could have indicated this by pressing the semicolon; but with the template 
in place, you have to hit the right cursor key some number of times, or 
have a right-one-language-token key -- which is still no more convenient 
than hitting ; would have been!

Everyone always uses for loops as an example of where syntactically-aware 
editing would be useful, but to be honest I've never found anything more 
elaborate than autoindenting and automatic closing brace/bracket insertion 
to be any help at all.

Those identifier autocompletion dialogs are even worse, because unless you 
have a hyper-high-end system they make the editor stall for an instant, 
they tend to dump a dialog box up on top of your typing (why not open a 
pane at the bottom of the screen and fill it up?) and they invariably 
don't contain the identifier I'm actually *looking* for anyway. So the 
result is a juddery, flickery, annoying mess, like browing an advert-laden 
site with animation enabled and flash installed. :)