Is it better to use a keyword with low search volume and very low advertiser competition or use a keyword with average search volume but high advertiser competition?
Nope, just use keywords with a high search count and low competition. That is a way to conquer a lucrative niche that will help you rake in more money. The hard part is to fiend those keywords. You could use MNF. Great tool but you have to pay for the pleasure of using it.
I'm looking to do a website on fishing, unfortunately all the keywords have high advertiser competition and average search volume. So I'm stuck with the keyword options from above.