Balance Clock Tree Skew and levels of two different Block implementation in Encounter

Hello everyone, 

I have two blocks separately implemented using the Encounter.

They have huge CTS Global skew and i am unable to balance the CTS of two blocks and having hold violations between the very shallow paths having communication between the blocks.

This is due to the number of logic elements in the two block. One block has 160 FF and simple in design and other has 550 and complex block in terms of logic.

Block 1 : CTS : 1 level : Min Trig Skew: 20 ps , Max Trig Skew: 40ps
Block 2 : CTS : 5 level : Min Trig Skew: 300 ps , Max Trigger Skew: 400ps

It will be helpful if you someone can share how to balance (small skew can he handled in post silicon tuning) the CTS of two blocks to avoid top level CTS flow as i want different clock port for both blocks.

It will helpful if any reference to balance the CTS in hierarchical design (current implementation) and top level CTS (future implementation) can be shared.

Thanks,
Sachin