"Movies like Megiddo are a great start in my opinion."
They're a start. On the other hand, you have "The Passion of the Christ." Compare the two films, as regards quality of presentation.
One was seen by an enormous audience. The other was seen by a small minority, even of Christians. Consider the reasons for the difference.
Quality will win every time. Quality will be seen. Mediocrity will simply not be seen. Making mediocre films is a waste of money and talent.
Good Christian-themed movies have long been made. The Robe, The Lion in Winter, Ben Hur, just to name three very quickly. All were made by major studios, by major directors, and acted by major actors of their time. All were huge successes.
Nothing else will do. Megiddo will not live on to be seen again and again. It failed in its mission, since only those who already see it as semi-prophetic even bothered to see it. Quality is essential, and in every facet of film-making. Anything less will fail miserably.
With the range of entertainment options out there, it takes an exceptional production to get people to make whatever effort it takes to see the production. Anything less fails.
It's not Hollywood that's to blame, quite frankly. It's a failure by all but a few Christian film-makers to actually produce a film people want to see.