No, don't invest on any expensive equipment yet. Get your channel's direction and value preposition set first. I mentioned value preposition a lot when reviewing other people's channel, and I do that because I see many of them struggling to grow, and when I visited their channel I see why - they don't show people a clear enough reason to subscribe. I visited your channel and saw some random videos and some let's plays, they don't tell me why I, or anyone else should care about them or subscribe to you. I mean for example, someone might do botany on their channel, I'm not into botany, but I can see why people who are into botany would probably like to subscribe to their channel, if they show a good enough reason for people within the niche to subscribe.
It doesn't matter if you have the highest quality mic in the world if you can't offer unique values in your videos for people to care in the first place. I'm not saying you shouldn't do what you love, but try to create things that are fundamentally different with them. You can't just do things that everyone does and expect growth. GradeUnderA for example, who has more than 1 million subscribers and all he's using to record his voice is his cellphone, according to one of his videos that I watched. And the graphics on his videos were most likely made using MSPaint. How? He's being creative.
So, think about it thoroughly first, about what you love to do, and how you want to do it. Then after you start getting the hang of it, start investing in equipment that you know will help you create better contents and achieving your goals. Also, try watching YouTube's creator academy videos and the official YouTube Certified Consultants' videos, they should help you a lot in understanding the do's and don'ts in growing your YouTube channel.
Good luck
