The difference is that now it takes 1h to get 2 energy.
Before the patch you would get 2 energy in 20 minutes. It means 6 per hour. With 6 energy you used to fight three times. In your example you would have 42k in one hour. The more you fight, bigger the chances to drop a girl, so you are making less money and fighting less times, so increasing the time you need to get girls. Theoretically, the chances to get girls have been calculated to be the same, this is yet to be seen.
And you also get 6 fights in the arena in one hour. If you win these fights you get stuff. I don't know exactly what it is, since I didn't win a single one today.