Invoicing website for freelancers holding page feedback

Hello, I am in the process of building an invoicing website specifically for freelancers running small businesses.

My problem: I am an independent freelancer and contractor and I have to invoice my clients. I use invoicing software and it gets the job done. It was exactly 7.3 million features and is very overwhelming, all I want to do is create invoices and get paid. I pay around $70 USD per year to create invoices, download them as PDF's and send to my clients via email (with no watermark, which looks unprofessional).

Solution: I want to/am building a platform that allows you to create attractive invoices in the same manner and track the status. The product will be free forever no matter what (no watermarks, no ads, no nothing). The twist is that, if you want, we can make it easy for your clients to pay. The way it works is we send a scheduled (controlled by you) email to your client with a pay me now plz link that goes to a payment form. If they pay using this link, then all you pay for is the transaction fee (at cost price).

Whilst I am building this product (what do you think by the way?) I want people to register their interest so I can contact them shortly before launch with a special offer. I have created a landing page for this (https://invoicemyclients.com/landing). I am looking for constructive feedback/advice/ideas please :).

Thank you in advance