In 1A, Regulus really brought nothing to the table that the other demigods don't.
When the +200dmg gloves and the AoE wossits got removed, he lost the ability to be big autoattacker. Torchbearer has plenty in the way of ranged control, as does Rook (with Boulder Roll). TB brings some pretty good AoE to the table too. UCB can be a monster autoattacker, and with recharge items can be doing ridiculous damage pretty much all the time.
The only thing Regulus really has is a ranged slow on weak attacks and the ability to stun if he can lure someone over a mine (and mines recharge too slowly and cost too much to be a truly useful choice).
He really needs some adjustment to bring him to the level of the others, if nothing else.