You’ll have some issues using Webflow Memberships with this due to your structure.
With digital products, Webflow Memberships is a good option when you are selling just 1 digital product for download, versus access to many / all digital products on a page.
Memberships attaches to ecommerce for payments.
Ecommerce can either do one-time payments (physical goods or digital downloads), or subscriptions.
With the latter (subscriptions) you’d be good to go for your setup, but it sounds like you want a one-payment for access to all digital products, yes?
If so you’ll need to come up with a hack to make that work in Webflow Memberships. Totally doable, but it’ll take effort and not be too solid.
You’ll also start bumping into unexpected issues like these:
No you don’t still need to use ecommerce.
You can use the free Webflow Membership accounts and bolt on Stripe yourself. The flow would be to setup a Stripe Webhook that triggers a Membership invite on successful payment. You’ll need to also remove the ability for people to register (self-serve).
Memberstack
A better approach, based upon what you’ve said, is to use Memberstack. It’s much more flexible and will give you what you’ve asked for on all 3 of your points.