Is It Worth Fixing?

Hello, I have a Gen1 MobileStudio Pro 13 that I bought in 2017. I did have to get the battery and screen replaced a few years after while it was under warranty. However, the battery has started swelling recently, and it’s very worrying. It’s no longer under warranty and it’s too expensive to go through Wacom to fix. I’m kind of scared of using a heat gun in order to disassemble it as I’m not sure if that will make the battery worse. I also have to mention that the SSD has also been slowing down more in the last few years and has become sluggish, which makes me wonder if it’s beginning to fail. I'm wondering if it’s worth fixing it myself, or replacing it with a newer model or a comparable Windows-based tablet computer?