PS/ I was looking into buying a new mac (probably an Air) since this one's from mid-2012. But other than the hinge, my current one works great. I'm waiting and hoping that the ****** butterfly keyboard gets replaced (maybe 2020? Fingers crossed!) so I can buy a decent laptop to replace this one.
It seems I did an optimal job in 2012 by future-proofing this device, giving it extra RAM etc. so it still functions efficiently while being a pretty perfect computer all round. It doesn't seem physically possible to do such a good job today. If I buy a high-end Windows laptop I will sacrifice not only mac's OS but having a perfect trackpad. Whereas if I buy a mac, I sacrifice a functional keyboard. So it's impossible to just buy a perfect and up-to-date laptop since the butterfly keyboard came out. It's such a shame. Apple has the best trackpad in the industry bar none, and it had perfectly good keyboards before. Mine's still as solid and satisfying to type on as ever following daily use since mid-2012.