Hi Rob, It all depends on what you want out of your theme, There are tons of free themes out there, that may do what you want. Remember its basically your content that will be bringing in any traffic you receive, not your theme. However if there is something special that you want from your theme, and the paid one is what does the trick, then its up to you. Best wishes on your endeavors.

Sure you can share to Pinterest WA blogs you desire.

yes you can, just set up a Pinterest account if you don't have one yet, then using your Affiliate link, you can share anything from WA, or from your website:) Here some training here...
https://my.wealthyaffiliate.com/training/how-to-add-a-pin-to-pinterest

Actually I get members ranking way higher than I do because they are here every day just about, asking crazy questions that they could look up in the question bar above. I myself ask way too many questions because I'm ignorant and can't find the answers. But the member I am talking about came in a month or so after me and is ranked twice as high as I am just because he is here all the time, asking silly questions, or leaving articles about how his dog has been.
The ranking is to get members to help other members. What you get is a gold star. Not sure what else. I'm pretty sure it has nothing to do with money though. But to get ranked you have to be on here a lot helping others, blogging, giving out information, or writing helpful articles for other members. Also I think following helps. The member I'm talking about has followed everyone on the site!
Are you here to rank? Or to make money by growing a business. I have to ask.
Rick
Good luck!

Your ranking here at WA is based off of your activity here. I don't know exactly how it all works nor do I want too, but here is the overview: When you create blogs, discussions, or trainings that helps, being active helps, and answering questions and participating in conversations helps.