I had my shooting shoulder replaced 10 weeks ago, so recoil is something I have to be somewhat careful about now.
but I want something with more horsepower. I'm considering the 28 Nosler and 300 Norma.
This should be your primary concern in my humble opinion. Yes the replacements can be a functional improvement but they are not like the original equipment. But, it's your body and you should enjoy hobby.
Before I offer my opinion I will tell you that one member in particular has the experience from competition:
https://www.longrangehunting.com/members/jeff-heeg-osoh.111250/
I enjoy shooting the longer ranges and I have both my shoulders intact so far.
Your choices, 28 Nosler and 300 Norma Mag, are fine with the .300 Norma Mag. being one of my favorites. I certainly would look at the recoil of both given bullets and powder necessary for the 1 mile targets. Remember that powder as a component of recoil calculations is often referred to as 'ejecta'.
I used the 26 Nosler (which no one discusses anymore) with the Warner 121 gr. Flatline, now 123 gr., through a 30" barrel. Good performance and a milder recoil than the heavier bullets. Then I switched to the .300 Norma Mag. using the Badlands 205 gr. SBD2. Lots of fun but more recoil. I can use the same cartridge/bullet combination for hunting and target shooting.
Currently, I'm shooting the 33XC in a much longer barrel with heavier, higher BC bullets. This might be a little on the high side for for what you're looking for. There are several threads available here to read.
Enjoy the process!
You might consider a suppressor or properly designed brake to help mitigate the recoil.