I know that in pnp otilukes freezing sphere only has a radius of 10 ft, but in DDO where we have to judge distance at a glance 10 ft doesn't leave much room for error. I wouldn't expect it to get the radius of a delayed blast fireball or anything, but increasing the radius to 20 or even 15 feet would help this spell a lot.
Heck I would gladly trade back the extra dice increase we got on the spell in the recent spell pass if I could get the radius of a delayed blast fireball with it.