Fixing Minecarts for Survival Mode with Booster Rails

Since the introduction of the elytra, it has become by far the best form of transportation in the game and while many other transportation items have found their uses, minecarts never really have.

Last year, Mojang made a great step to fixing this problem by allowing you to set Minecart speed via gamerule. While this is great, "traditional" players who don't want to use commands in their worlds are left in the dust and are still stuck with the slow minecarts. A simple solution to this could be simply increasing the speed of minecarts, but this creates a new problem since players who have builds that may rely on minecarts going 8 blocks/second would no longer work.

Therefore, I propose adding a new type of rail to the game: booster rails! This type of rail would have its speed altered depending on the strength of the redstone signal. Every redstone level would correspond to +2 blocks/second. So at a redstone level of 4, the minecart would go the already existing maximum of 8 blocks/second. You could also make it lower if you wanted a slower minecart speed, or you could increase it all the way to 30 blocks/second, making it significantly faster than the current speed.

This new rail would take over the crafting recipe of currently powered rails, while powered rails would have their recipe replaced from gold ingots to copper ingots. This also solves an issue players have of powered rails being too expensive.