I try to use google keyword tool and find some micro-niche keywords with low competition and search volume of 400-1000 searches a month.
does competition matter when writing articles or is it better to just try and get as many backlinks to your article as possible
Of course, competition matters, but try to put in your keywords in your article the natural way. You can try to target other keywords for your site as well. It's like a matter of trial and error.
yes you need to put content in your article but content seem to be natural write dont put unnecessary keywords. maintain keyword density
I read somewhere that your keywords shouldn't be to competitive, what amount of competition is desent enough to rank well with. Also that it is a good idea to submit your articles to bookmarking sites and to ping the url of the article. How does one do this?