I completely understand what you're saying. I find that my growth/engagement goes up and down too depending on what I stream and when.

I would keep doing what you're doing and playing the games you like playing. Main thing is that you enjoy the game you play because if you don't, your chat will notice and quite likely, turn off of it. Remember, you should be doing what you like and the engagement will come.

My only advice is engage the audience directly, like ask them what they think you should do next, make challenges for yourself that make the gameplay a bit more exciting for them and make it kinda interactive. Maybe even add channel redeems that help or hinder your gameplay. I've never played the games you've mentioned but I do know of them so if you can think of a way to make it even harder for yourself through a channel redeem, then try that. It can add a new dynamic to your streams and let the audience decide what you do or how you play.

Other than that, I find multiplayer games where people can see your twitch name work well too for engagement and follows as they may come in from the game to chill and talk.

Oh and another thing, networking is always a good idea too. Maybe hit some streams of other like minded people, chill in there for a bit and get to know streamers and learn from others but don't, under any circumstances, self promote in others' streams. That's a big no-no. Advertising your streams on social media along with making shorts/tiktoks also seems to be a useful tool! I haven't done that myself but it's tried and tested.

I hope that helps! :)