Getting shot through solid cover

I have seen this happening to many players on youtube like being punched through closed doors and think it definitely is something that needs looked into and also I have had players who are just extremely laggy and bouncing all over your screen to where they are nearly impossible to hit and in most cases they are exploiting the lag as the kill leader, i think removing the option to choose any server above 30-50 ms would help solve this issue as I checked the servers one day and had options to choose up to 200 ms servers which shouldn't be possible