I would ditch the hasted regeneration. As the DM are you ever constrained from not using this? Whould any reason exist to not include it in every monster of this type? Not that I can think of. Leave it out.Regenerative: As a full-round action, a Sand Golem may bring any sand or fine soil to their bodies, allowing them to regrow any severed limbs, and regain 1d6 hp. All limbs are regrown after the first round, and they continue to regain 1d6 hit points for every round that they do nothing but gather sand.
By adding Haste to the spells cast to animate the golem, and adding 50 pounds of sand to the amount required, the time required to start this ability is reduced to a standard action.
ConstructionI would put in a crafting requirement, can you say "Sand castle"? You can sculpt sand. And I would make it 300 pounds of sand. Having moved a few 50 pound sand bags around they do not have that much volume.Sand golems are possibly the easiest golem to create. The only materials you need to create one is at least 200 pounds of sand. No crafting of it is required, as once animated, the golem rises up and forms itself out of the sand.
CL 10; Craft Construct, Animate Objects, Haste (optional), Caster must be at least 10th level, and must expend 3000 XP.
It's an interesting variant to find in a desert environment or some such. You might add that in a sand environment they can dissipate into a pile of sand until the conditions for them to act are met. Great guard for the desert King's tomb. The PCs start messing with the seals and sand starts forming into golems, it's going to be a bad day.