Upgrading to iPhone 15 Pro

I have an iPhone XS Max that has served me well since 2019. My battery has recently dipped below 80% and has started to give me trouble, so I’ve been looking to upgrade within the year to a new phone. Want to stick with iPhone just for simplicity and familiarity, plus I keep the same phone until it doesn’t work or get supported anymore so it’s an investment.

I was looking into getting one of the 15’s and was stuck deciding on the 15 Plus or the 15 Pro. Pro Max is a little too out of my comfort zone for price, and I feel I might like the size of the smaller models more. I’m debating on the 15 Pro like I said, but I have some concerns about the battery compared to the price I’d be paying. I know it’s still great, but I was wondering in anyone’s opinion would I be better off getting a 15 Pro or waiting until the 16 Pro (eventually) comes out? I’m thinking it might be more efficient and if it is it’ll be an instant pickup. I know anything would be better than my current phone, but just want to gauge everyone’s opinion on what they would do. Thank you!