Do think starting to read out loud and mimic sooner has large effects on fluency development and speaking ability? I know not everyone enjoys reading out loud but I’ve always enjoyed it. It’s definitely something I want to put into my daily habits.

I think mimicking is extremely valuable early on (and later, actually). I would even go so far as to say that it's the most valuable thing a student can do when it comes to pronunciation. Reading aloud is different, though, because it's so ridiculously hard until you get to a fairly advanced level. Being able to read a novel aloud with some fluency without practising is quite difficult (I stumble when I do so, although not so much that a friendly listener will mind). I don't think it's good pronunciation practice for "normal" students simply because most of reading aloud is about other things than pronunciation. :) I wrote about it here: https://www.hackingchinese.com/reading-aloud-in-chinese-is-really-hard/