DXF to DWG

Hello,

I wanted to add several .dxf into one .dwg drawing without having to add the blocks one by one and I found a solution on an old thread using a VBA module. It works, but the finale dwg weights more than if I had done it adding one by one. (1,6Mb compared to 800kb)

Is this normal?

Is there any other way to add multiple .dxf into one .dwg without using the VBA?

If it helps, it is a cartography I am trying to assemble.

Thank you