There have been lots of good suggestions so far, but one thing you’ll want to consider before getting a split keyboard is whether you type “correctly”, because

There have been lots of good suggestions so far, but one thing you’ll want to consider before getting a split keyboard is whether you type “correctly”, because if you hit the Y key with your left hand, for instance, you’ll have to retrain yourself to use your right hand instead. As for key switches, you’ll certainly want to try out any mechanical options in person before you buy to see if you like the feel and if you can handle the noise factor—my local Micro Center has a tester keyboard with a bunch of different kinds of Cherry MX switches to see which you like best.