I don't know whether Paul route will have big impact on the main storyline!!but there is a really hard hitting plot points in the main arc where Lisa has to rise or mature herself to save her loved ones!!(in my view of the future story)
Tony and his men are really gonna be a nightmare for Lisa ,when compared to Paul,Paul is nothing!
Palegrass has kept bad guys in the shadows or yet to reveal in the storyline ,i m waiting to see what their real calibre is!(and hope Lisa will be learning a lot from them)
I think we aren't yet at that stage but hope it will happen in 5.xx,6.xx where we won't be seeing naive Lisa anymore!