My opinion and some questions.

[Paolo_A]

2. DIRECTLY tell them/ask them for RP. Yeah, seriously. PM them "Bro, can we RP?" or some shit. "I'd like to resolve this through roleplay instead of bangbang, are you kay wif dat?" But don't be let down when people "cba to RP," it's a plus on you for trying.

Very good point here, that's the original way of initiating long ass roleplays (with strangers mostly). Even tho people say 'PM ISNT RP OKE' it makes sure both parties know what they're dealing with. And if not for roleplay details, you can use it to estimate an approx. time period so nobody will be surprised or disappointed if someone has to leave suddenly.