God created all things in such an ordered way that we can use science to determine cause and effect. He also gave us a superiority over all of creation by granting us many abilities that only human beings have. He gave us free-will, not so that we could do wrong and get punished accordingly, but so that we could freely choose Him.
God has done so many wonderful things for us that we take for granted. Sounds like most parents with their children. God indeed shows His fatherly love for us in so many different ways. Sometimes, in the smallest of ways and other times, in grand ways.
So, why ask if God is an all-loving father or just an all-powerful lord and master? Sad to say, but it shows a difference between Christianity and Islam. In the end, we try to imitate that which we hold most sacred. So, while there are no doubt many, many good Muslims out there, having faith in a God that is an all-powerful master lends one to try to do the same to others.
I know that there are plenty of Christians that may act this way, too. But I would maintain that most of them do not hold God to be the most sacred thing in their life. It could be money, power, or any number of things other than God. When God is an all-loving father, the closer that we get to Him, the more we reflect His love to others.
“You shall love the Lord your God with all your heart, with all your soul, with all your mind, and with all your strength.’ The second is this: ‘You shall love your neighbor as yourself.’ There is no other commandment greater than these.” – [Mark 12:30-31]