Advice for Photo editing software needed.

I purchased an M5 with 24Gb of ram. I was using a unibody from 2012 but finally upgraded. I’m not a fan of the subscription model used for Lightroom. I bought Lightroom in 2014 and haven’t needed anything else but now I need something new. What should I go with? I would like to buy something once and not pay monthly. What are my best options here?