Is cool! I digg the little planet 
OK, one thing you can do to immediately improve both look and SEO, and you already have done half of the job.
On your grid of cards you have the repeating Check it out button. Link button, same text everywhere. It’s as bad with SEO (because the text is of a lower importance in HTML, and doesn’t carry any meaning) than with design (because you have that repeating object everywhere, sort like a CTA but if you put 20 CTA on your page you’re losing the benefit right?)
You already have a hover effect on the whole card : good! That’s what’s suppose to replace your shiny big orange button. And that should be the unique interaction. No hover on the title for example. And the link should be the whole card. That’s an issue with your sharing badges that are on top of the card… They’re a bit too showcased if their importance is secondary. If the main goal is to click on the card, don’t let them in the way, find another solution toplace them.
The best for SEO would be the link on the title of the card. H1 or H2. So instead of having the link on the title plus the button, put the links on the card itself and the title.
And this should at the minimum be a H2
And if it was me this would be a h1 because it represent a complete content, an Article in the HTML5 book.
You can accentuate the interaction by bringing your orange color to the background of the card when hovering it. This way you will only have 1 card with orange at a time.
And your images don’t have a ALT description, it’s very bad!
For anything related to sales, think like a google robot. it doesn’t see your design, just the code. only the code. Read your site with CSS deactivated you will see
You need to understand the structure and everything, and where all the links go.