Whatever you do Phily, do not sign LeBron. LeBron's presence at a franchise completely changes the direction of that franchise for better or worse. But right now, the direction the Sixers are headed is the right one. You may have choked against the Celtics in 5, but you still won 52 games and have two future superstars in Joel Embiid and Ben Simmons.
If you want to sign a marquee free agent... make it Paul George. He would replace J.J Reddick and give you a deadly tall ball starting 5. And unlike LeBron he may buy into being the second option on offence, as he's already been through that with OKC and Westbrook.
I think the teams that really need LeBron and have the pulling power to get him are the Bulls and Lakers. The Knicks too, if Kanter declines his player option. Pacers and Mavericks have an outside chance at getting him also. Now watch both players take their player options rendering these last three paragraphs moot XD