At first, i used apt-mirror, but it's not customizeable enough so in the end i abandon them. Next, i asked the maintainer of Kambing, one of the biggest online repository in Indonesia and he told me about debmirror. I tried to use this and yes, it's very customizeable. I can download only the selected architecture, something that is not yet supported in other application i tried before. It saves so many spaces, since the repository itself is very huge.
A full Lucid repository would take approximately 60 GB and by filtering the packages to selected ones, i can reduce it to around 30 GB. That's 50% reduction which is very nice efforts.
Let's hope the mirror can be launched and used before Lucid Lynx is introduced in the end of this month