For me ⚡ will always be the Lightning symbol, which should not be conflated with sats as a unit. 

For example, when I buy things at checkout I choose ⚡ to indicate I want to pay over Lightning as opposed to on-chain. 

I use sats as a unit account not just for Lightning but also for base layer and ecash. 

Zaps are Lightning transactions. Intermint swaps are also Lightning transactions. 

The current sats symbol comes from 丰 which means fullness or plentifulness in some East Asian languages. It's one way Satoshi's name can be transliterated. Personally I like that. I also think it's easy to write.