I've been playing Counter Strike since version 1.1 ( 2000 ) now a 16 year veteran of this amazing game. ( voted as most skillful FPS, still around ) My average KPD ratio over this time is 2.44 with an average hit percentage of 26.5% My most noted skills in CS/CSS are as follows

1, Map Awareness
2, Spacial Awareness
3, Movement Skills
4, Weapon Skills
5, Voice Com ( team tactics )
6, Reactions
7, M4 Specialist ( I have mastered this weapon over 14 years )
8, Playing as a CT


Noted Weaknesses

Only spent around 10 - 20% of total playing time as a T ( so much weaker generally as a T )
Can be limited with other weapons ( 70% of total playing time spent using an M4 )
Limited sniper ability
AGE I'm not getting any younger ( now 40! )
limited knife skills ( never been any good with a blade )