1. There's no longer a +1 bonus for magic weapons; instead, you simply add your Strength score to melee attacks. 
2. I have replaced instances of ADVantage and DISadvantage with +1 and -1 to be more immediately recognizable.
3. Changed "ambush" to "surprise" to be a bit more generic and added the adjective "unsuspecting" before "NPCs" to give GMs clearer flexibility to rule that surprise is not an option

EDIT: Forgot to add I also took away the stipulation that rangers can’t use melee weapons. Seemed too harsh.