I think this wouldnt change much cause the props spawn inside the game, dont they? I could be wrong about that
Nah right outside the red entrance of Prophunt
Thing is the BLUs can see the REDs in the prophunt area through a glass window, if the prop windows were added BLUs would know which props to look out for and which not. IDK if this would tip the minigame in BLUs' favor more so this is more just an observation than anything else.
Prophunt is already incredibly unfair for the reds. Even if they were added it would barely change anything in terms of balance.
I could be slightly wrong since its been years that I last played Prophunt in TF2, but there are some things to consider.
First of all you can shoot, throw and swing around with your weapons as much as you want, and you will not lose any health doing so. Normally you would lose HP when playing on a Prophunt dedicated server which means you had to conserve your Health if you seriously wanted to find people.
Then theres the fact that the amount of natural props is incredibly scarce, with the only area decently decorated in props being that little shack next to Burger King. It makes it very easy to realize when something is out of place.
Armory is closed off, meaning that ammo is not limitless, but you don't have to check every prop with bullets, fire and explosions. Just by focusing on a prop, a name may or may not appear infront of the screen. Being a spy or medic with the solemn vow can make seeking even easier.
Then there's the disadvantage for the reds where they have like only 30 seconds to find a spot, meaning no matter what, some spots are just impossible to reach before the seekers are let out.
And Lastly you cant lock your prop in place, so checking for guards by moving your mouse is very risky depending on your spot.
So "tip the minigame in BLU's favor more" is a massive overstatement.