Simple suggestion that came to mind when thinking about how player scavs and the flea markets flow.
As a lot of the changes BSG have been implementing seem to be on slowing down the endgame, which is basically already here, 2 weeks into the wipe. I think they've done a great job in slowing it down so far, but it's here again, already.
A lot of players, myself included, once they hit 20, will scav in a lot more, either when I have gear fear or no friends playing, I'll do scav "Stash runs" every 20 mins. Over a few hours or maps like woods or shoreline, the RNG and pure no-risk high, fairly consistent reward turns it into an insanely profitable way of making money.
I think the stash loot tables are good, I think the scav timers are good, I just think the balance of being able to scav in with zero risk, and turn a huge profit is broken, just because you can flip them on the flea.
How about, as soon as you hit 20, and have access to the flea, all items found in raid from a scav run lose their FIR status. You can no longer jump in, loot amazing items at zero risk and flip them.
The only people this change hurts are people who already have access to the entire lootpool of tarkov through the flea, meaning they have to grind more to get ahead, as they have to sell to traders (Which isn't a bad thing by itself) slowing the snowball effect, otherwise, you have the infinite money strat of using the scavs to purely fund your PMC, which I don't think is the intension of BSG given the direction of "Scav karma". Yes, this would suck for the "Found in raid quests" which is why you flip the "FIR Status" once people hit level 20, after which, there really is no excuse that you can't go in and find those "FIR" items.