I am sorry I do have to say..on Ballistic Blades..always...Damage, Range, Damage...why take explosive...Why do you want to wait for something to die in a few seconds when it could die right now? ( Man, I sound like I live in Texas )
Two reasons: First, the explosion has an AOE and can damage/stagger other enemies. And second, the explosion offers an additional stagger - which shouldn't be necessary if you're facing one enemy, but is very useful when you're facing three of them.
Anyway.... blasphemous builds, huh?
I just mentioned this in another thread, but I sometimes put a PPR on my Krogan Shaman and spec him for maximum shield recharge rate, with absolutely no melee upgrades whatsoever. That's as blasphemous as they come.
And I don't get the point of the OP's BatSol build. If you're going to skip grenades on him, why not do a melee build? The combination of Blade staggering and DR from Blade Armor and heavy melee makes the BatSol an excellent melee kit. If you're just shooting with him, it makes no sense not to take at least a few ranks in grenades. It's not "unique," it's just gimped for no reason whatsoever.