Quality over quantity seems to be the best bet. But as long as it's not a ridiculous amount, go for lots!
in my opinion, you are build 20/day; however, your site is not open new. you have new web site may be 5/day.
you need unlimited backlinks no limit to gain backlinks ... in the begining you need minimum 100 backlinks a day .... after some time you will get auto backlinks .....
get as many backlinks as you can limit of getting backlinks is just a ridiculous myth after some point, people will talk about your site and you will get automated natural links
For some project i add even 100 / day to my 6 year old site. I've got some good results using voltrank.com and limit of 20 / day, which helps my weight loss blog move up.
Be consistent, but think more about the sites' PR, the diversity and relevance of sites, and all the other basic rules of link building.