Is it strange that I want there to be a God ?

[CleanShavenJesus]

Why shouldn't you disprove that the two largest religions which both point to extremely similar deities who trace back to similar historical figures must argue against the existence of some common entity that explains both?

Well, if that were the case then it would mean that neither Christianity NOR Islam is true. If you can't prove one correct, then they're both incorrect. If you're getting at the idea that there is some sort of God that Christianity and Islam both represent, but in different ways, you can't say one is correct and the other isn't. They're similar, not the same. There are still a plethora of differences.

If there is a God that Christianity and Islam are, in a lack of a better term, "on to", then your religion can't be true, and neither can Islam.