I am wondering if I should upgrade from iPhone SE 2 to 16.

Hello everyone. The weather is cold these days! How are you all doing? I bought an iPhone SE 2nd generation in May 2020 and have been using it since then. The problem is that it slows down after upgrading to iOS 16, overheats after upgrading to 17, drains battery even when surfing the web, etc. I haven't even tried initializing it for various reasons. I heard that restoring it by connecting it to a computer in DFU mode is more powerful and cleaner than a normal reset! The cable is also defective, but I usually use AirDrop to transfer files without a cable, so buying a cable for that is a bit inefficient! Anyway, I would like to ask you guys whether it would be better to change to iPhone 16 or to get AS for SE 2 and use it for 2-3 more years. I am visually impaired, and I don't have anyone around me who knows about Apple devices, so I would like to ask for advice here. For your information, the current software is 18.1. The speed has become slower after upgrading to 18! My current phone doesn't have Apple Care, and the repair costs are high, so I'm wondering how I can get it repaired cheaply.