You are on the right track, and the numerous guest blog posts are a good start. Your landing page definitely needs work, though - both in terms of visual design and conversion optimization.

One great way to drive more traffic back to your own site from guest blog posts (since that one link in your bio won't get many clicks) is to create an offer *specifically* for the readers of that particular site. Take for example your guest post on letsgrowleaders.com. Spend a couple hours bundling up some content (could be a PDF download, a template, a worksheet, etc. - feel free to get creative here) that caters specifically to that audience ("3 Project Management Templates for Leaders"), and then embed that offer at the bottom of your guest post. Be sure to get permission to include a call-to-action for that offer from the folks you're blogging for, of course, but crafting a unique offer for *their* audience will often win their approval.

I'd also recommend building out a module to collect email addresses directly within the post in addition to linking to your own landing page for the content -- it should help you increase your conversion rate & collect more emails.