We could significantly reduce powered rail usage by using spin boosters on all lines:
Instead of using manual switches, use a detector rail to automatically start the delay timer and then launch you after you you speed up. Then stick a second detector on the exit to reset the rail for the next cart that comes by. If one booster is not enough to get you all the way there, add another booster along the way. Configuration will be a bit complex since we'll be using a bi-directional single rail instead of a double rail, but it shouldn't be too hard to figure out and would save a lot of resources.
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