It already works this way. A 1,000 lb bomb has a larger effective blast radius than a 500 lb bomb for example.
The Crater size might be the same. (cant remember the actual numbers) but i have tested the blast radius.
I will try to dig up the data i compiled as to bomb crater size and effective blast radius.
I do sem to remember the 1,000 lb bomb crater size being around 30 yards/90 feet