Well, I think the problem is that Melton is a rookie drafted in the second round. We do not know what Melton's skills are in the NBA. Setting that aside, the original argument is quite interesting. I think I agree with Phraz. Booker is the primary playmaker. Suns don't need a young Ason Kidd (without the "J"). They need a Derek Fisher to Kobe's Booker. Bring the ball up the court, pass to Kobe (Booker), stand in the corner and be ready to hit open threes. Defend on the other side of the court.
It gets a little more complicated depending on the makeup of the roster, starting unit, etc. I know he is gone now, but I'll use Chriss in the first example. If a combination of Warren, JJ, and Chriss are your starting forwards, then you absolutely must have a shooter at 1. If Bridges and Bender are your forwards, you can probably get away with a point guard that can't shoot. We also don't know if Ayton is gonna be able to hit jumpers to open up the middle for Booker. I think he will, but we don't know. I just don't think you can survive in today's NBA if only one or two starters can hit 36% or so from behind the line.
It also gets complicated if there is no other facilitator on the roster. Teams could double/ pressure Booker, in which case, the PG would need to facilitate a bit. This may not be a huge issue if Ayton establishes himself as a real low-post threat, which I do think he will.
This is a really interesting discussion. I maintain that with Booker's play making, along with Ayton's likely low-post presence, the Suns need shooters around them.