I am also a believer in ID/Creation. Since neither evolution not ID/Creation can be duplicated and thus not proved with 100 percent certainty, a degree of faith is required to believe in either model (they are not theories, as you must realize). Without the possibility of proving either model, one is left to examine the evidence. There is plenty of evidence to casts serious doubts on the evolution model; so much that it would take a great deal of faith to believe it offers a rational explanation.
ID/Creation cannot be proven in a positive sense. While I may seem far-fetched to many on the surface, having faith in it is a viable position if for no other reason than that the statistical odds against evolution are so great as to be incomprehensible.
This does nothing to 'prove' ID/Creation, but if evolution is eliminated, it leaves ID/Creation as the only viable possibility, unless someone can come up with another possibility; one i have yet to see put forth.
Aside from this, my belief in ID/Creation rests primarily with the consistencies and historical truth of the Bible that are so persuasive, at least in my mind, that belief in ID/Creation isn't much more of a stretch. Sure, believing in ID requires some faith, but not nearly as much faith as belief in evolution.
Why do you believe in space aliens? Possible, yes.