Right. As of now we can only go by theories and such until we've tested all the Master Classes for bugs as well as changes. However, I will explain the changes to Turtle.
Turtle Book: The thing with the Turtle Book is not just about the max refill in RP, but also the fact that it locks the player to going with a female. Now I'm not saying this is a bad thing per say, but it's still a little stupid. Since a lot of good points were made about keeping Turtle Book, I figured I would suggest this kind of change.
Both Genders: Using the Turtle Book refills half their total RP. If your RP is currently an odd number (like say 5 for example) you'd get two RP balls and half of your bar full. Since max RP atm is 7, that would mean you get three RP restored while having half the bar filled for the fourth one.
Males: Keep the old effect the same: increase attack but lose LP for the duration of the book.
Females: Instead of raising defense like in old DBO, raise Hit Rate, but keep the EP drain.
Nerf: One of the big things that made Turtle Book so good is that you can cancel out the effect and reuse it after CD finishes. This made the drawbacks of using Turtle Book pointless. As such, I suggest that the Turtle Book cannot be deactivated at will like a debuff. This way you can't spam it for RP and have to suffer the drawbacks that come with it, but at the same time be able to utilize the benefits that come with it.
Super/Giant Kame: The reason why I suggested that both skills go in a straight line is not just because it makes more sense, but also to give opponents a chance to escape incoming Kames. At the same time, having Super/Giant go in a straight line allows you to "pierce" through mobs who are in your way. The fact of the matter is that while it won't have the AoE effect, it will still have a similar output in damage since you can basically plow through multiple enemies in front of you. Final Flash of the Fighter tree has a 10M width in a straight line, which is still a large coverage area. Given that Giant Kamehameha has a 15M AoE, making it go in a straight like would actually increase the amount of targets you can hit at once. It would actually be nice to test this out with Final Flash and Big Bang Attack since Turtles lack any form of skills that go in a straight line.