Just for kicks, I did a custom top 100 for games from 1985 - 1995.
40% of the top 10 were not a licensed theme. That's a pretty solid percentage I'd say. Interestingly, 40% of the top 20 were not licensed.
If you look back at your history, what percentage have been a licensed theme i wonder? I've only had 1 (granted, my collection is more by what's for sale locally than anything else, and not a great deal of money invested).
I don't think a company needs a licensed theme per say, however, I do understand the "draw" it has with many.
I'd like for American Pinball to succeed, whichever direction they feel they must take.