Indeed.There is a case to be made that entering at 3pm makes G+ more valuable if you it to its fullest.
If a park opens at 9, by 3pm you'd be booking your 4th LL and just be getting to the park.
If you want to go on *the most rides,* get to the parks early and use G+ for the next available ride every time you tap into a reserved attraction. Keep doing that throughout the day. The downside: the most popular rides book up fast, and so, by the end of the day, your only choices will be C-tier rides.
If you want to get on *the most E-Ticket rides,* grab them as they become available later in the day. And every two hours grab the next one. By mid-afternoon to the evening, you'll be able to 'walk on' top tier rides one after the other. So, you can wait to enter the park later in the day, or, go earlier and just get on line for the C-Ticket rides will lesser wait times.