Definitely in favour of something like this, though I have no strong opinions about which framework and don’t want to undo work you already started. If I was to start work on it myself, I’d probably use Slim, as I’ve been through the same silex migration process on my personal site. Briefly tried Symfony Flex, got annoyed at how bulky and overcomplicated it was, ended up using Slim and php-di instead, inspired (but not completely based on) this slim project skeleton and my use of slim for the taproot/micropub-adapter example

I'm definitely a fan of Slim. I've used Slim3 for https://github.com/gregorlove/indiebookclub and several projects at work -- and used Slim4 for a couple of work projects. I haven't revisited my Symfony Flex code in a couple years, so let me check to see how far I got. I suspect not too far, though, and I'd be in favor of starting fresh with Slim4.

I'm working on the Slim4 migration this holiday weekend.