There is no shortage of text editors from the basic like nano to more
advanced like Kate or Kwrite. Gedit is basic, but with a GUI. Each person
has differing needs which is why there are so many. You could also look at
Gnote which is Tomboy without Mono (avoid this if you can). It has wiki
capabilities. There is also Leafpad (simple), Scribes (more advanced), Zim
(advanced with wikis) and Basket which is KDE's equivalent of Gnote.

For general purpose I recommend Kate. I use it almost every day. I also
like Scribes which is GNOME's answer to Kwrite.