I don't know what exactly you meant by martyrs, but if they died doing Allah's will, than I hope I will be one of them.
This world is not a way to measure things. Our reward is paradise. This life is a short test.
6:32 And in no way is the present life (Literally: the lowly life, i.e., the life of this world) (anything) except a plaything and a diversion, and the Last Residence is indeed most charitable for the ones who are pious. Do you then not consider?
I know a person who is doing Allah's will dies happy and in peace with himself. Do all people having millions of dollars and everything they wanted in their life die happy?
All of Allah's creation are subservient to Him-- not only the angels and jinn, but all of His creation. There is no free will; not even Allah is free, because He is constrained in Himself, having one unchangeable, indivisible will. God introduced Himself first, as "I AM". Mankind is in the image of the Most High, saying "we are". And this is why the messengers remind us again, and again saying, "The LORD, your God is One." As mere ignorant men, we perceive ourselves as the gods of the earth, doing our individual wills.
God is God, and His creations are His will being done.
Happiness is God's to give and take. He gives what He wills, and everyone and everything will continue in His will.