symfony-docker VS Plates

First, there is no "official" Symfony Docker image. You're probably referring to https://github.com/dunglas/symfony-docker, which - although being maintained by a core team member - is not an official image from the Symfony organization.

No, server setup is not my thing. I stick to official Docker image, works perfect.

I have an Symfony application running in docker container using dunglas/symfony-docker-Template. (https://github.com/dunglas/symfony-docker) This Template is currently using Caddy for managing ssl certificates and http & https connecetions.

Just thought I'd ask here for recommendations for any helpful base images or existing projects for reference. I'm not really a symfony/php person, so any advice other would be helpful too. I'm definitely looking at this symfony-docker project, but I might just end up using the official php 7.2 base image.

Here is the idea: let's say I have Symfony application using this image. But other people, non-tech ones, interested in this app would have to install Docker too even though they only want to run it and see it in browser.

As others mentionned, I can only suggest you to go with Symfony, it meets all your requirements. If you are looking for a docker config out of the box, this one is my favorite (done by one of main Symfony's maintainers) - https://github.com/dunglas/symfony-docker Very simple to install, use and deploy later.

I'm using the official docker install: https://github.com/dunglas/symfony-docker and I'm trying to install doctrine using symfony flex.

Official docker image, check for yourself.

I used combination nginx + caddy but I consider to drop nginx and leave Caddy because it's a reliable web server for production use. Also I found good github repo with docker config which makes it much easier to setup https://github.com/dunglas/symfony-docker

I use PHP with Route, the Plates template engine, and my blog posts are markdown files grouped by folder (year/month/day.md).

If it's a simple project you could try Plates. Escaping is a little more verbose, but you don't have to learn any new syntax since it's native PHP.

✅ Plates

Start reading through PSR standards and see if some (not all) of them sound like good ideas to you, and write a mini framework of your own around those ideas, with composer to import high quality third party packages such as Plates.