Two Currencies (HC/RX)
Two-sided capitalism is buying ingame items with "Robux," or any form of "hard core" money, like USD. This means that a group could hold both currencies. The group can collect USD from Robux using the DevEx. For example, there are these "Utopian Guns." Let us say that you have to pay 100 US dollars to obtain them. You would have to connect a bank account to your account. Just like Robux has a commision, hardcore money would as well. They would go to the "credits" section of the account, where it could be loaded onto a bank account. For suggestions, one US dollar would be worth 80 robux. These purchases and bank account connections would only be available to the upper class, as is comprable to Roblox's ToS and rules. This would allow developers to charge dollars and/or Robux for an item. These US dollars would be a "second currency" on Roblox. Downside: Roblox could lose profit and Robux may lose the war against USD! (hopefully not) This adds a new market, the Roblox hardcore currencies market.
Buying Games and Places
In my opinion, people and groups should be able to buy and sell places for Robux (or USD, if that is what they want). For example, with this system, a Roblox billionaire could buy MeepCity from Alexnewtron (if he was putting it up for sale). This would add another market, the place market. It would also be available in trade.
Philanthropism
Roblox should allow people to give Robux to each other.