If thermals are your concern why not get one of the 17 pro phones instead of the 17 since it has an actual dedicated cooling system and aluminum unibodyThe 15 Pro has a bad thermal design and is also so titanium so it doesn't dissipate heat well like aluminum does.
I have the 15 Pro myself and just dumped it for the base 17. It has such horrible thermals. The most disappointing iPhone I've ever had.