I’m assuming you’ve played the ealier version. The reason for the control layout is two both make it simple and streamline options so players wont have trouble switching to other characters. The uniqueness of character come from subtle things as you mention like normal range,throws properties ect For example Lucy A 6 attack has extended range on her normal with no hurtbox while Lucy B has slow overhead with follow up that juggles and side switch. Many games sport similar layout and still achieve the results of having Diverse cast. (Phantom Breaker Extra, Smash, DBFCI, Shin Kohime, Zatchbell/Gashbell).
Their is free cancel system in place with 1A and 5A. The combination of 1A>5A> Directional A (8/4/2/6) was three hits for free. count in the fact you can do jump then thats 4. The fact you can dash cancel into short hop can let you get in 8 hit combo for just 25% by doing jump in attack>1A>5A>6A> Dash cancel hop normal> 1A>5A>6A.
It’ll be difficult to allow different throw system with out it overlapping other commands. I think the limited control over throw also done so player don’t default to it and instead should aim for mix up if want to maintain a certain positioning. Have juggle throw is also Lucy B specialty. Personally I’ll like it if the knockdown period for throw just to be extended.