Profile of rodicc

Hi guys, I'm a new player and i have picked up playing Ostheer as my first faction that I want to get good at. After watching a bunch of casts and reading trough some of the guides i find that a lot of people suggest getting a flamer halftrack as the first light vehicle to put pressure on enemy infantry. I, on the other hand, have found myself almost always choosing to build a 222 Scout Car instead as it seems that it can provide at least a bit of help against enemy light vehicles while being also good against infantry.

So, my first question would be when and why would you choose to build a flamer halftrack instead of the 222 and vice versa?

The other thing I have found myself struggling about is when I am falling behind in the midgame and get to building medium armor. I would always try to field a Panzer IV first, but if I am running low on resources I go for a Stug III instead and that is where my second question comes in.

How do you make the most use of a Stug III against enemy armor, as I have found myself mostly getting outmaneuvered if I choose a Stug, and falling behind even further?