We've been running e-commerce for the last six years, and have tried everything (woocommerce, open commerce, bigcommerce, magento, prestashop).
They are all light-years behind Shopify.
We've had bumps along the way with Shopify as well (similar problems to yours).
A few thoughts:
- Know who you are in bed with : Shopify Payments is actually Stripe Platform in most locations, and PayPal in Europe. We refuse to work with PayPal because of their predatory behaviour, so we choose not to use Shopify Payments in the EU.
- The Shopify Payments platform is for better or for worse a "start without friction, KYC later" experience. Be aware of what this entails.
- Get on RocketReach, find key people in Shopify relevant to your problem and send a succinct email asking for assistance. It's unblocked every problem we ever had
- Do the same with your merchant processors : Edwin from stripe actively reads HN, and can often provide assistance on Stripe related issues.
- Get lawyers. Not the Go-Sue-the-Pants-off-everyone lawyers, but business / commercial lawyers. Not only can they provide excellent advice for your business, they often spécialise in these types of situations to have conversations and results that you can't access individually.
At the end of the day, know your business partners and establish a relationship with them.
Using a combination of the above, we've survived competitors using fake C&Ds against our processors and platforms, amongst other things.