Disclaimer: I work for a similar SaaS that targets a specific industry and integrates hundreds of APIs, and I previously worked for a similar company.

I see that you are targeting 18 industries but how are you going to disrupt online sales for each of them?

Imo Shopify (and the software that is typically used along with it) are dominant enough that your best chance at building a VC-backed store builder is targeting some niche (market segmentation).

The reason is that, for each industry, you are going to get clients who are already consuming some SaaS that solves online sales, and are looking for something that integrates it with a cherry on top - dashboards, insightful reports, notifications, task automation, etc.

Good luck!