good idea to increasing your site traffic to remain online on bookmarking site, social media site and forum discussion sites will get you a lot traffic..... first two idea on this reply are also good one...
Include relevant content, relevant to your page description and Meta keywords.. Instead of changing your URL or redirecting from your old URL to your new URL, follow Google's procedure on URL changes to make sure your new site doesn't get skipped, or just avoid URL changes if you can..
Organic traffic will give you stable and long term results. but it will take some time to get organic traffic. you need to analyse your competitors to get some idea about organic rankings. Social media gives you quick traffic but it's for some time only. I would suggest you to do both simultaneously so that you will get traffic for now with the social media and long term positions in search engines with organic optimization.