I am wondering is it possible to get a same number of elements using "sweep" technique, even the two models have different size of excavation?

Here are the two examples where the size of irregular shape of the excavation is different. 

The small one ​​​​​​​has 30100, the large one has 31080 elements.

The only thing I know about it is to control a number of local seeds, where both has same number of local seeds, but it doesn't work in this case. 

Can anyone give me a tip for this?

However, when use "Structured" mesh technique, I am able to control the number of elements with different geometry model.