Charge lacks an option of the d20 rules: at the end of the movement you can do a Bull Rush action with a +2 bonus.
https://www.d20srd.org/srd/combat/specialAttacks.htm#charge
in the Attacking on a Charge paragraph.
In the game the only option is Charge Attack, so the character double the movement and does only one attack. Increasing the options could benefit strong but slow races, like the dwarves and the half-giants, expanding their influence in the battlefield and giving them more options than fight in close quarters. Also a plus point for the high speed races, like the Centaur - they can cover more terrain and reach far enemies with a nice little bonus to incapacitate them.
Charging demands removing obstacles so to do this new option teamwork will be required to clear the line of movement. It's not a free you double your move points. Positioning the character will be more important: any hole in the formation could open a direct way for an creature to throw an enemy into a pit. Battlefields with damaging tiles or with variability in heights will be more interesting.
A difference with the d20srd and this game is the "Greater Bull Rush" feat: here offers a bull rush as a swift manoeuvre one per round - so with the new (Charge + Bull Rush) option, the character could do two bull rushes per turn, one before charging or just after finishing the movement plus the standard. Doing it after charging should give the +2 bonus to both bull rushes? Would it be overpowering? In my opinion the +2 bonus should only be applied to the first of them leaving the option of doing the second Bull Rush after the charge but with the normal modifiers.
This option could also be a little extra to creatures and classes that gain the feat "Frightful Presence" or similar when charging - an additional condition on top of the Bull Rush will make them a serious menace when a path freed of obstacles is opened. If your are considering giving the Barbarian more options, in D&D3.5 and Pathfinder certain totem variants get "Frightful Presence" so it could be a buff. At low levels get it when charging and later at will, for example.