But those aren't God's values. He kills, causes harm,
Who did God harm?
Who did He kill?
and has taught us no cures. Shouldn't we all strive to emulate that sinless perfection?
The Prophet pbuh did mention several herbs and oil to help fight diseases.
Prophetic Medicine - Lifestyle & Wellbeing According to the Quran & Sunna
Elsewhere we read:
Abu Hurayrah narrates that The Prophet pbuh said:
“There is no disease that Allah has created, except that He also has created its remedy.”
Bukhari 7.582
Usamah ibn Shuraik narrated:
“… ‘O Allah’s Messenger! Should we seek medical treatment for our illnesses?’ He replied: ‘Yes, you should seek medical treatment, because Allah, the Exalted, has let no disease exist without providing for its cure, except for one ailment, namely, old age’.”
Tirmidhi
Taking proper care of ones health is considered by the Prophet Muhammad pbuh to be the right of the body.
Bukhari as-Sawm 55, an-Nikah 89, Muslim as-siyyam 183, 193, Nisai
The Prophet not only instructed sick people to take medicine, but he himself invited expert physicians for this purpose.
D.o.H. p.50, As-Suyuti’s Medicine of the Prophet p.125
From this brief beginning one would gather that Imaan (faith) and Tawakkul (trust) have to be the uttermost important part of a Muslim’s belief. Hence, problems, illnesses or troubles of life, should be very easy to cope with. But, since this material world has been classed as Darul Asbaab (A world of means) it is necessary to take medication for one’s illness. In most cases Mufti’s would give a ruling of suicide for one who died in the event of not taking medicine. We all would be required by Shariah (Islamic Law) to have trust in Allah but search for the cure, which would be classed as the highest grade of Tawakkul – Trust in Allah.
Then we should strive to be godlike and inflict leukemia onto people as He does to test those people's mettle, right? We have a right to know if they would pass the test. And we can be assured that we would not be sinning since it is godly behavior.
You who believe! be upholders of justice, bearing witness for Allah alone, even against yourselves or your parents and relatives. Whether they are rich or poor, Allah is well able to look after them. Do not follow your own desires and deviate from the truth. If you twist or turn away, Allah is aware of what you do. Qur'an 4:135
You who believe! show integrity for the sake of Allah, bearing witness with justice. Do not let hatred for a people incite you into not being just. Be just. That is closer to taqwa. Fear [and respect] Allah. Allah is aware of what you do. Qur'an 5:8
Say:
“My Lord has commanded justice…” Qur'an 7:29
So call and go straight as you have been ordered to. Do not follow their whims and desires but say, ‘I have iman in a Book sent down by Allah and I am ordered to be just between you. Allah is our Lord and your Lord. We have our actions and you have your actions. There is no debate between us and you. Allah will gather us all together. He is our final destination.’ Qur'an 42:15
And many more verses showing we have to be just.
And when it is said unto them: Make not mischief in the earth, they say: We are peacemakers only. Qur'an 2:11
As humans we have no right to be like God and decide who goes through what test.