Okay, I have a few things to say on this
"It's sick that we lost most of what Rome, India & Persia offered the world because of Christianity & Islam."
I'll agree with you on Rome and Persia, but I disagree on India. Jalal-ud-Din Muhammad Akbar was the 3rd (?) ruler of Mughal India, and he really set the tone for respect and peaceful coexistence between all religions in India, including Christianity. Much of the destruction came later, when the British were conquering India. That might have been what you intended, but India as a whole wasn't harmed too much during the Mughal invasions, not to the extent Rome and Persia were.
Also, since the Mongols weren't initially Muslims, I'm going to consider all comments on the Mongols irrelevant.
My position is that overall, the Arabs were better warriors than Christians. In open combat, Christians almost always lost. However, I view this is moreso because of two things 1) Bad tactics on the hands of Christian leaders and 2) Superior technology that the Muslims had (Composite bows, horse archers). The combination of the two meant that early on Christians couldn't respond to their disadvantage with innovative tactics, and thus lost.
I mean, the only reason Islam is around today as a major religion is because of the environment it was formed in. When Islam broke out from the Arabian Peninsula, the Byzantines and Persians had just finished a decades-long war, and the Byzantines had won. So what did the Byzantines do? Stopped paying the tribes on the border to be their watchmen. So they didn't give the Byzantines warning when the Arabs marched through. All of a sudden, Damascus was under attack, the whole Levant fell in a matter of years, and Constantinople was under siege. What did the Byzantines do afterward? (I think in the 1000s now, when they were on the upswing against the Muslims). They dismantled their very successful "farm" system of raising and training troops. It was very much a feudal system, but they didn't replace it with anything. They just got rid of it, because the Emperor at the time feared the military.\
But I rant. Muslims historically overpower Christians, but major successes on both sides must be taken with a grain of salt because oftentimes one power was stepping into a vacuum of power caused by internal divides or weaknesses