So your standard fighter in PF1 are almost solely focused on damage, as playing defensively just means you get ignored and your friends get picked on. But now with shields being more useful and more defensive options are being opened up, I'm wondering if a entire party made up of different fighters would be viable. Of course it would fall behind a properly balanced party in most encounters, but with how flexible Pathfinder is becoming I think it'd work pretty well. Here's how the party would be made up.
Spear Fighter: Focuses on killing monsters as quickly as possible from behind the shield fighters using reach, possible also tripping monsters and using AoO. High STR for damage, and CHA to be the face. Half Orc or Human, no Dwarves.
2 Sword and Board fighters: They'd be the frontline and protect the rest of the group from attacks. Being able to use their reactions to keep enemies from getting around them would what would probably keep the part alive, and using the Shield stance that allows them to keep up their shields forever without spending an action would allow them to help kill monsters. High CON and STR, maybe INT to unlock Combat Expertise if it's still a thing and to provide skills for the group
No Elves as you need the highest CON possible, so probably Dwarf or Gnomes.
Archer Fighter: Shoot enemies from a distance/ pick off ranged enemies and spellcasters. Would get feats like Point blank shot, or the one that removes the penalties for firing through allies' squares. High DEX and STR to maximize damage and hits, also focus on WIS to be the parties Ranger basically. Elf or Dwarf would work pretty well.
This is mostly just for fun and I'd need a lot more information to actually get it more set in stone, but if you have anymore ideas on what could make this more likely to work feel free to share your ideas. Also if you have any ideas on other entire class parties then be sure to share!