It's a good idea and kind of works. It shouldn't change in that respect.  

The first ten pages you're showing your characters lives.  So, the story hasn't really begun.  The inciting incident isn't supposed to come till page 12 - 17 (17 is late, but still viable).  If the reader could see 20 to 30 pages,  the notes on characters (first ten pages) could be more detailed.  

The first ten pages might look right. By page thirty problems in the first ten might stick out. 

The reader wouldn't be forced to read 30 pages. They'd just have the option if they desired. 

Well, what I did in the ten page reviews was to show 13 pages, with the last 3 having a grey background.  So, a reader can read a few extra pages beyond the 10 to try to get context.  In that way they can do the review in an hour and earn 4 TalentDollars.  It is all a balancing act, George, some scripts are so bad by page 10 that little needs to be said.  But, true, others may have complexity and not get to the goods by then.  However, if the writing is good and the characterizations are good, the reader would be able to say they would want to keep reading, and that is a good sign for the writer.