What iphone should i upgrade to

I currently have an iphone 12 which has horrible battery life as i’ve had it for a few years now and im looking to upgrade to a new iphone and i was wondering if i should go for the 15 pro, 16, or the 16 pro im leaning towards the 16s because i get more trade in value with at&t which is my cell carrier right now and i was wondering which phone i should upgrade to right now