There are several eCommerce [PHP] frameworks available and in our opinion it really comes down to Magento vs a bespoke-solution. We are not anti Magento, but unless you are locked into this `system` we'd opt for a much simpler system. Why ?
Cost and management. Most eShops really do one thing and one thing well which is to `shop` = present products in a searchable way, a single-click to buy and a simple checkout process. Much more than that and you might be turning your on-line shop into another web-application which probably merits separate or micro-sites.
There is a general consensus in the market that with Magento `anything is possible` and that's naturally true with any PHP framework, but unless you are reinventing the wheel, we don't really believe that Magento is now worth the time and the effort when far simpler systems are available and just as adaptable without the hugely over-engineered Magento framework. If you love Magento then stick to it and naturally it has worked for you.
Unless you are budgeting tens of thousands on your new eShop, we strongly recommend a custom framework as an alternative. It's so much faster to use and understand and more importantly as developers, much [much] easier to code and customise = far lower cost base for you.
With so many off-the-shelf eShops available these days [and a lot of them are very restrictive and for end-users only] it is quite a big ask for an eRetailer to invest a small fortune in a framework designed for international corporations. With a custom framework, API, backend PHP/MySQL dashboard and with the right focus and development, there is little you can't do.
A simple and highly adaptable database of fifty+ [not two hundred] tables, backend API so you can choose a JS frontend, e.g. React/Angular or any modern framework and last but not least a clean and micro-service PHP backend with a MySQL schema [all EAV so completely customisable] is a far simpler way to develop your bespoke eCommerce systems. We call it vShop and you can visit it here