I'll start, since no one else wants to. When I chose Military unit, it was quite self explanatory, since back then ST6 was the only one around. Now, I stay there since it is an official branch of the Government. As for my party, I don't really care about what they claim to be, since it's hard to live up to party standards in this game. I just chose the least populated one at that time, DSP, since I wanted to be in a chat area where it's not clogged with spam about sub for subs and selling messages

As for Military Unit, I chose ST6, mainly for its supps and activity, but then I left to help my friend run his own MU, which incidently I also had to help fund. As for a political party, usually I don't care about the ideology of the party as most don't actually do much to actually show they represent their ideology. However, on this server I founded DSP to offer an alternative to the Conservative Federalist Party, with our small membership, it has been hard to organize and until now we've just been trying to survive, but I plan for all than to change relatively soon.

In Indonesia you cant choose party and MU

That is possibly because nobody has made one yet.

or because it is occupied