I think there are 2 broad categories of code editors:
(a) The ones that translate between design view and codes eg. Dreamweaver. You can switch to preview/design and just resize the boxes or tables visually, and the code behind will self-generate.
(b) The ones that just purely for coding, with auto-completion etc.
I think in category a, I have come across another one JetBrains Webstorm, i think it's paid version. It can be slow just like most of the (a) category editors, because there's a lot of heavy processing behind running it.
Category (b) editors are actually pretty lightweight. Sublime Text is pretty lightweight and with the plugin self picking, makes it a little bit like a Linux system. However, I must say sublime still contains occasional bugs, particularly in the plugins, as this is sort of open source contribution. And one must know how to configure things to get Sublime working beautifully. This includes opening configuration files using Notepad and editing it, unlike your run of the mill software, where you have a Preferences section to tick and untick or set certain values. Sublime by default without any adjustment is pretty bland and dumb, just like a notepad. Only when plugins configured properly, you will have auto-completion etc. However, I also have mention that using Sublime's autocompletion is a little different than others. There are times, the auto-completion requires you to press certain shortcut key combination in order to appear. And it is not like those Visual Studio etc, where as type, it will popup by itself.
Notepad++ seems to be packed with powerful commands, but it's again, not very intuitive and may need a certain learning curve or getting used to.
I like the fact that Notepad++ seems to be about the only tool I tested to be able to open large files, ie. larger than 1MB, like Log files, without hanging.
Favorite Code Editors for web Development?