Well in Nottingham, England
We use slang for pretty much everything in day to day life and heres some smoking slang we use:
Smoking = Blazing
Strong Weed = Grade, Peng, Dengle, THE piff (Piff itself is just weed but THE piff is a good, strong smoke)
Weak strong weed = Yaegen
Rolling = Strapping, Billing, Building
A spliff itself = Zoot, Jay, Bifter
I know theres a catogory between strong and weak weed but we never get that middle ground.
Here in Notts we get the best or the worst depending on who you go too.
Thats all i can think of for now, i may come back later and add more lol