E-commerce to SAAS. Need guidance on the best platform to build my app(s)

For the past 5 years, my focus has been e-commerce. While I do not have direct programming experience, I have project managed multiple open source platforms (Magento 2, Akeneo, Odoo, 3CX) as well as built out and integrated these systems using Zapier.
While working on these projects over the years, I have realized what I truly enjoyed was the process of building these systems and less about dealing with supply chain and other issues that go along with e-commerce.
Like most people here, I have quite a few SAAS ideas I would like to pursue, but for now, I have one that I want to put my efforts in.
With that said, I am needing some guidance on what would be a good language to build my SAAS on.
I have looked Bubble.io and I know there are quite a few Python developers I could contract out, but not sure if that is the right direction.
The core function of the SAAS app would be to create simple design templates similar to Mailchimp or Klaviyo which would connect to other applications via Zapier and/or Inegromat/Make. That way when triggered the output design will be custom to the lead/customer.
Would love some feedback on what program language would be ideal to create a design SAAS app.

Thank you in advance.