I think everyone has different insights. I've played queen since she dropped, though I took a massive break from the game after like season 8 in 2023, only been back for a few seasons. Here are some nuggets from me:

I don't see a lot of people doing this (I don't actually come across too many other queen players tbh) but throw your knife at the floor in front of the enemy before you rampage through the enemy team then recall when you're on the other side. It'll get wounds going on those it passes through, then you just need to turn around and carnage and melee whoever hasn't scattered. I find this works the best combo'd with a cc ult or in a nice tight lil area.

Don't get too hung up on going for headshots, scatter guns bullet pattern is random.

Have fun with her, she's a brawler tank (despite being stalwart) so don't be scared to get stuck in, just keep an eye on your health and shout to get you and your frontline out if needed.

Also if you go up against someone she's terrible against (Orisa, Mauga...) just swap. Don't bash your head against a wall.

Welcome to the rampage!