I also think it is a terrible idea.
@Colt
It introduces a barrier to entry for new players. Granted it is annoying when a low level player joins and dies, but I've seen poor players that are level 6 and great players who are level 2. There are tons of other decent ways to deal with the problem of new players joining hard difficulties, a few of which already exist
Clearly you arent playing on Hell of Earth or even Suicidal. Just last night I was playing on West London on my own server when 5 level zeros joined on wave 8 just after shop time so I didnt have time to kick them, and then some died instantly and the others just disconnected right after joining leaving me with 250 specimens to deal alone as support ... -_-
And just yesterday I was forced to kick about 50 (NO exaggaration) low level characters mid-game causing me to lose precious shop time and sometimes even getting me killed while in the player menu. I have even changed my server name to say "Levels 5-6 ONLY or kick!" and they STILL keep coming in masses. Passwording the server is not an option because I want everyone else to be able to play there, and the perk replacement mutators are buggy.
While some level 6 might be bad players they at least spawn with a weapon, require way less money and do way more damage so changes for survival are actually higher than for a so called good level 2 player. And btw I havent met a SINGLE level 2 player who would have survived on HoE, not even my friends who reseted their perks. Im not saying its not possible, but its HIGHLY unlikely that such player would join your game (seeing as in 800 hours I havent seen one). Hell I even used to give a chance to all low levels when I was just starting on higher difficulties but based on experience they always died on the first wave they played so its beter just getting rid of them right away.
The problem I see with this is that some people have inconsistent levels. For example, I am level 5 Shapshooter and Medic, level 4 Commando and Support, and then level 2 Firebug and Zerker. Would the filter look at your highest level perk? Or would they all have to be a minimum level? I would like the option, but I'm not sure how it would work exactly.
The way I see it, you should be able to join a server as spec with any perk but in order to join the game youd have to select a high level perk. This way anyone who doesnt have them couldnt play and would then (hopefully) disconnect.
But if you have level 5 sharpshooter and every other perk low level, then you SHOULDNT play on the higher difficulties, simple as that. Sharpshooter is the fastest to level up so even a newcomer could have level 5 after only a week of playing...