Most guitar players who start out with songwriting will start out with chords, logical as most guitar players start out with playing chords in the first place when learning to play the guitar.
After people have written their fist few songs they may start to feel: “I need use more complex chords, chords such as extended chords which contain 9ths, 11ths and 13ths”. 
Learning about chords, their basic construction and what to do how to extend them is not wrong but most of the songs you like have been written with basic chords. Chords can be played in various ways and how you put those chords together is another matter. Too many “pretty chords” in a song may be a bit too much. Select them carefully for them to make a contrast against the rest of the harmonic landscape of your songstructure.

A useful approach to songwriting is to use all what you know and to use it at its best: Once you have a chordsequence experiment with the strums: Does each chord need to be played for one bar or should I try playing two beats for a few chords? Experiment with the arrangement of your song: It is a common feeling to be happy once you have your order of chords, there is this feeling of accomplishment. Great, but maybe the songstructure could do with some extra work? Record the song for yourself and listen back to how it sounds like. When you listen to your song keep the listener in mind. Is the song fun to listen to?

if you have only written a handful of songs do not worry so much about what I mentioned before, as your songs will start to get better the more you write.

Over the next few articles I will give a few pointers as in what may be a good approach to writing, giving you a few more, extra techiniques you may want to try out for your own writing.

Keep on reading and hope to catch you soon again,
Eddie