The length doesn't matter, the link bait will serve its purpose as long as it interests a lot of people and get a lot of links.
Improve your site contents...make it more informative and make your site more catchy and can get attentions of the visitor that will make them go back or will make them link to your site....specially when your site is related with their site and you have great information to offer...
Link bait is basically content that a mass of web users find interesting enough to read and link to. Create something useful, informative or entertaining. Promote it, and hopefully it will get the attention it deserves. Good luck!
Once you have your article look to submit it to as many press release sites as you possibly can Do a search for a directory of these sites theres loads about