My weapons are the same as they've been for ages: Blaster + Agoniser

But if I'm choosing something from the Craftworld armory, can I just have a Prism Tank?

Sorry that is not a weapon, only a Vehical ;]

Ugh. I suppose I should go look at your armory. Singing Spear is the clear winner in melee, but I'm not familiar with your ranged weapons (aside from the Shuriken weaponry). My guess would be either the weapon of a Fire Dragon or a Ranger.

Singing Spear.

Such beautiful music they make.

Melee weapon wise I would have to say Mirror Blades which is just a pair of Banshee Power Swords,
Ranged weapon wise Shrunken Pistols/Rifles after all how can you beat a weapon that shoots mono molecular ammo and is shot using the Eldar psychic ability, much less of a chance of someone taking your gun and shooting you with it.

You can have the Prism Cannon I guess.

or the hand held ones used by the specters

My mind.

There are handheld Prism weapons? Are they Forgeworld only or something?

Yes, the shadow spectres use prism rifles and are forgeworld only.