I guess you'd make a similar amount of money if you get people to pay for the mods, or if you will accept donations for them ... with the big difference that with things people pay money for, they will demand things to be top notch, with good service etc. With donations, it's more of a "Thank you for what you've done, I hope you continue", than a "Hey I payed for this and I must have it working before tonight, c'mon I'm waiting!"
I've had a number of people asking about donating to me for my mods, but I've replied to them that at this moment, I don't have any use for the money, that I've only released mods to the public that I myself want.
And said that they should either keep it, or donate it to another mod creator or Rickard instead.
So, really, I don't think you will get that much difference in income, and no licence worries either
But ... it's impossible to tell what lies in the future, but this is kind of a guesswork/gut feeling I have ...