What % traffic increase can I reasonably forecast

I am looking for thoughts on what a reasonable monthy traffic increase % would be - employing pretty basic on-site and off site optimization techniques (no paid ads).

My boss would like to establish a monthly traffic goal for the site (and my pay would be based on reaching these goals). We currently stand at around 25000 visitors per month, the plan calls for us to hit 120,000 by end of year (increasing by abt 30% per month).

I am not sure these numbers are reasonable, any thoughts?

FYI: our website is a wedding planning website (elegala.com)- and we are targeting keywords like wedding planning, wedding dresses, wedding flowers etc. - which all get considerable search volume. We used to get about 100,000 visitors per month, but traffic fell substantially when we relaunched the site in Jan. 08 (we renamed urls - but employed 301 redirects...)

You'd be crazy to agree a target based on visitor numbers - almost as crazy as them for suggesting it.

ROI counts; conversion counts; targeted visitors matter too - but bums on seats is a loopy way to incentivize SEO efforts - and a guesswork-related trap for said seo.

Quad is right, you can't put a number on this, but you should set goals. There is much that needs to be done to get your website SEO up to par. It has many issues, and they can be fixed. What I usually find is that the boss wants the SEO done, but won't let anyone make the needed changes, and with this site those changes will be drastic. Is he willing to make drastic changes.

Thank you for your response. We are willing to address issues and make changes(provided they do not involve high cost to fix). Are there any major issues that you can point out to get us started?