First of all, where is this need for money coming from? Looking at the CS we have at least 16 Galleons and the priciest thing we can buy right now is a potion where the Ingredients cost 5 Galleons, which we can't even make because our potion level is too low. There is no dangerous magic that we can study right now that will break our bank. So we really aren't hurting for money, especially since we now charge 15% on our Hogsmeade trips instead of 10% like before. We are actually doing pretty well. And I doubt that we will come across some project that costs 100 Galleons to fund anytime soon. Basically, lets not make a problem when there really isn't one as we aren't hurting for cash.
Secondly, while Fred and George want money, they aren't suicidal. Yes, they want money, but they make it by gambling, probably getting things for people like we have been getting things for the younger years from Hogsmeade, and from inventing Joke Shop items that they sell to their fellow housemates. They don't make it by hunting dangerous magical beasts in the Forbidden Forest, killing them, and harvesting their organs and bodily fluids to sell. That was never once something that was hinted at as being in their character. There are lines that are too far for some people, and I think the Twins likely stops before it comes to skinning animals in a forest students are forbidden from entering.
Think of it like this. In a mundane setting, one day a loner kid comes up to some twins from a poor family, whom he has never talked to a day in his life. He then asks them if they would like to go into a forbidden forest with him to skin some animals in order to make money. It sounds crazy because it is crazy. Even in the magical world that is a bit out of there. We don't know the Twins, we don't trust them, and vice versa. And honestly, I hope we don't get to know them anytime soon. I like that our character is a little anit-social. I like the slow burgeoning friendship he seems to be building with Megan Jones and the possible friendship/rivalry there may be with Tracey. I don't want to start piling in more of the canon cast like the Weasleys, Harry, and Hermione and collecting them like Pokemon cards.
Basically, right now our finances our solid. If there ever comes a time where we are hurting for money then we will cross that bridge when we get there. But it isn't that time yet.
Anyways, on to another topic I was thinking about. I just remembered that this is 3rd year and that there are Dementors hanging around the school. As such, it might be wise to learn the Patronus Charm sometime this year. Obviously not right away as we also have a number of other things our our plate (school spells to learn, probably need to level up DADA and Charms one more time, etc.). But I was thinking we should consider learning the Patronus sometime after Christmas. January or February seems to be good time to maybe start attempting to learn the spell as it gives us enough time to whittle down the list of Spells and Potions that are needed for exams at the end of the year. What do you think?