For #2, just have all your heroes set at initial level of 1. Then, directly after you add the new hero, save the actor level in a variable and then change the new hero's level by that variable. So, if you are adding Alice to the party and Zack is your main character:
Change Party Members: Alice Add
Variable Oper: [XXXX: Hero Level] Set, Zack Level
Change Level: Alice's Level V[XXXX] Up
If you don't want it to be exactly the hero level, then you can just modify the variable further after you save Zack's Level
There is probably a way to do #1 too, but I'm tired and unfamiliar with 2k3.