Hi kccruise, and welcome to cruise-chat.
While it's true that Freestyle created a problem for group dining initially, NCL has worked out the kinks over time. Don't kick yourself about booking NCL. I see from your other posts that you are booked on N. Pearl, which is a great ship for families. I toured sister ship N. Jewel and the kids facilities were superb, including those for teens.
As far as dining in the no-fee, no-reservation restaurants, we've found that arriving within the first 15 to 20 minutes of its opening resulted in little to no wait, and a wider selection of tables. So, if you arrive early, they should not only be able to seat you relatively quickly, but may be able to find tables close by.
As for the pay restaurants, reservations can be made in advance, with the window varying depending upon the cabin type in which you are staying. See here
for another Member's response with the specifics.