5th perk slot IF none of your perks are "meta"
The devs could track perk usage and update the Top 10 list every mid-chapter.
If the player is not using any of the top 10 perks in any of their 4 perk slots, a 5th perk slot becomes available (perks in the Top 10 list are not available for the 5th slot).
Maybe the 5th perk slot can only be used to equip 1 of the 10 least used perks.
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I don't play the meta. I use niche perks and synergies, but I very often find myself needing just one more perk slot. It would be nice if the game rewarded players who don't take advantage of the meta and allowed them to have more build variety.
Comments
This would be too messy, I personally don't see it. Just run the 4 perks you want regardless, who cares? I don't think it's practical at all and nobody needs a reward for using something that is "non meta", and more people would whine and cry about perks being OP mimimi this mimimi that, "top 10 isn't enough, there are strong perks until top 50" blablabla. Would just make the community even more bitter in my opinion, sorry.
So I would use perk from top20 instead, suddenly they are better than top10... That will get them into top10 and suddenly you have a time to play actually meta perks with one extra. This would just screw statistics on perk usage.
It would be way better for survivors tho.
This assumes that the top 10 perks are at least 25% more powerful than all other perks, including the top 11th.
I'm not even sure how you can quantify that. Maybe if running a 'meta' perk gave you a 25% higher kill/escape rate. But that sounds absurd.