As Cai Morris mentioned, the labels are a bit far from the fields. I see you updated the form, it's a bit better but still far... not such a big deal though.
With the size of your text labels, you could really change some labels to be on 2 lines and it will still be centered well with each field. That's for labels with long texts. Nothing stops you from centering more that form and adding more emphasis on the call to action in green text above the form. I find that there isn't enough "impact", it needs to be more "Sign up now or you're missing something great!". Plus people need to realize that signing up first for these things is the best way to be a top recommendation... a bit in the same way as StackExchange; the older the account, the more likely people will get "passive" recommendations. Maybe I'm wrong and don't understand well what the site offers though, but that should still give you clues about what kind of self-interest you need to appeal to and how you can encourage people to sign up and share the site.
You could try some bold or just a little bit bigger size label.
Your form fields look great, very sharp and clean. The little icons next to the labels look good too. Nice colors too. Nice layout.
The form is short, if you ever add more fields to it, maybe it could be nice to make it on 2 columns, and even put the fields below the labels. It can be kept as it is on the side too, but 2 columns. Of course for mobile version, it will probably be one column.
Regarding your question about putting the registration on the homepage, I don't think it's a bad idea. Actually it's very good to not add too many steps between the call to action and the form. So I think it's good you keep it on the homepage, and at the first part of the top of the page. If you ever add more content below that form, you can always add a few call to actions that will send potential subscriber back up to the registration form. Personally, I like using full width ribbons with high contrast colors for this.
I like the explanations on top and maybe you could add a bit more small texts with description under each point or even some kind of graphics that could explain the process. For example, circles with names of entities and arrows going to one or the other. But keep a lot of text, the graphics should be an extra and shouldn't replace the texts.
I also think that'd be great to add something about why your platform is better than the others because the idea is great. For example, maybe show a demo or an access to it or a screenshot of the account section if any, mention the features, mention how people will communicate and who will be the intermediary if any, add a list or fake list of what hiring managers will see when selecting candidates so people who subscribe can have an idea of how they'll be shown to managers, mention how do people get paid (eg. Paypal, Stripe, by you or manager, etc.) and make it clear this form is for people who want to get hired; where do Hiring Manager go to subscribe and how do you select them? People who subscribe need to know you're not dealing with cheap managers who expect $3/hr freelancers. Add more details. This can be added below the form.
Since you have some kind of affiliate system, you could also illustrate with graphics and strong keywords what kind of money or online rewards "recommenders" get. Like showing a mini case study or how the "pyramid" works with imaginary numbers for the revenues. Make people dream of hitting the jackpot by signing up or appeal to their ego at least.