Well there is one more reason why I could never be a muslim.
If I may use this statement as an example, as it's not only yourself, but some muslims also have problems with islamic prohibitions when they go against their desires.
What I wonder is why we compete with/question the knowledge of the Creator? Over 1400 years ago Allah told mankind that the Universe is expanding. It took 14 centuries for science to confirm that. If the Creator parted perfect knowledge of the expansion of the Universe then would His knowledge about why dogs are impure, or pigs are impure or any matter, be flawed? Na udhu billah! It's us who need to accept that there are things that will never become apparent, ever. And their knowledge will remain only with God who has knowledge of everything in the heavens and the earth.
I don't know much computer jargon, but imagine the world like one big computer, and everything in it and that descends upon it as good and bad programs. We accept in our personal PC's that a bad program (virus) can corrupt a good one. But when Allah prohibits something, let's call the prohibition a firewall, people don't accept that the firewall is for their own good, and instead blame Islam as not being compatible with their lives.
Now imagine the angels of mercy as good program. It wants to install mercy in your home. But for reasons fully known only to Allah, this 'program' is incompatible with the program (your home) if you have installed a dog/picture in it. A dog can be bathed, prevented from eating it's own waste, and be cleansed from all the obvious things that WE THINK make it unsuitable as a pet, but there could be something about them, in their creation, that we don't know but God does, and that is why he has forbidden us from keeping them as pets.
We need to look past what little knowledge God gave us and accept that we can't comprehend the complexities of creation which include the unseen side, like the soul. Only Allah knows the formation of His creations and how they affect each other. All we have to believe is that God is greater than His Creation and His Wisdom and Knowledge are unlimited. So our duty is to hear and obey. And sometimes I get this hopeful feeling that in the here-after, maybe Allah will show the slaves who believed without question, the secrets of His creation which He'd kept hidden from them in the dunya. Maybe. Maybe not. Allah Alone is our Creator and Master. And that's all that matters.