If we got Melo, we'd be a team that losses in the WCF/WCSF each other, get to the Finals if lucky. We'd need a 3rd good player. If we got LeBron, we'd win the title, defense would not matter. But, what if we don't? What do we do? Get a defensive big like Andrew Bogut? Make a trade? Wait around for 2015? I am not a fan of that, it will waste a chance for Kobe to win a 6th ring.
Getting Carmelo on the team wouldn't ensure a title but it would at the very least make us a scary team if we kept our experiments this year and they panned out and got contracts here.
A team with
Beasley(if we got him this year)
Is a nice base and going into 2015 with more space when Nash's contract ends and Rondo and Love are available as well as McGee.