I completely agree. My wife and 8 year old son wouldn't play the full version of Pathfinder, too many options & too many rules. But this they can play and enjoy. I would love to be able to take them beyond level 5. I think to level 10 would be good for the next box. It could also include haflings, half elves, and gnomes. And add in another four classes. Maybe paladins, druids, bards, and sorcerers?
Heck when I discovered the Beginner Box, I read lots of reviews on it. I bought the PDF version and was so impressed when I finished reading it that I went right out and bought the retail version. I have not been excited about role playing in years, but this product has brought back the joy. I look forward to playing this whenever my family has a chance.