@sleepingcatte I'm not much of a system master of pf2, so caveats and grains of salt here. Most of my experience is in GMing, which from what I've seen of the things my players get up to, is just so much easier than trying to build a character.
The way I see it, the options are:
1. Full passive-aggressive. Ask your friend to build a character for you. When you show up at the table, hand them your character sheet, since they want to play your character so badly. Tell them you'll be back at the end of the session to grab any xp and loot. This is a joke don't do this.
2. Tell your friend that you appreciate their concerns, but you'd like to ask the GM and the rest of the table how important this type of character optimization is for the game that y'all collectively are playing. If they say just focusing on utility and control is fine, then maybe your friend hearing it from other sources will lead to them worrying less about your playstyle. If they say character optimization is important, especially if you're running through a pregen, then you may be in for some compromises.
It's never too late to stop and talk about things that were missed in a Session 0.
Are all of the other characters also under scrutiny to have all damage types? Does the archer have a wide range of elemental arrows? Does the barbarian carry a half dozen greataxes enchanted with fire, frost, lightning, etc.? Does the cleric have a special prayer prepared to take advantage of a peanut allergy?