I use BIAB for almost every batch, but of course, my process is unique. For one thing, I'm only making about 1.7 to 2 gallons per batch. That makes life very much easier. But even when I made bigger batches a few years ago, I followed the same process and it wasn't too difficult...
I place a large colander over a big plastic bucket. I place the grain bag into the colander. I sit down then carefully and slowly pour the entire mash volume through the grain bed. It takes a good long time, 15-20 minutes. This is how I "recirculate" to eliminate the small particles.
Then I also sparge, the same way.
See, I told you my process is unique.
Lately I've begun to experiment with just placing an extra grain bag or two into the colander, and pouring through that instead of pouring through the entire grain bag, so the small particles come out faster. Also incorporate a dunk sparge, and we should be good to go -- no small particles, sparged for efficiency... perfect. I should have been doing this for a long time already but just never really thought about it too hard.
There have been a number of other things going on with my process as well. Like mill gap settings. They say "crush till you're scared". Well I did that, for many years, and found I can easily get 90+% efficiency this way. However, I believe this comes at the expense of malt flavor intensity, not to mention, stuck sparges. So I have since opened the mill gap. Now I can sparge easier and still get decent efficiency around 80-ish AND get plenty of malt flavors.
But anyway..... yeah, I do my own thing. And you can too. We all make good beer. There's a million ways to do it, and no one's wrong as long as it all tastes great.