MM2 - Brave New World

[brell]

In room 16500, it bothers me a bit when skeletons come alive before Jack can get the rainbow key.  He must then return to the room above and back to disactivate the skeletons.
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As of now, my Jack has a good overview of the transit zone and some of the blue rooms.  He hasn't opened any door yet and and the gold bricks are on.  It looks like he can start at a few places:
1. Opening the purple door in 17099
2. Opening the purple door in 17300
3. Opening the red door in 16503. Jack knows about the green key in the room below
4. Opening the red door in 16704
5. Opening the yellow door in 16903
6. opening the blue door in 17302 Jack knows about the yellow key in the room to the right.

In the other rooms Jack does not know what will happen if he starts there.  So the choice seems to be between 16503 and 17302.  I do not see any hints as of which one to go for. Can the player assume that both choices are equal?
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It is possible to miss the purple key in 16502 if Jack leaves the room before taking the key.

17300: My Jack missed a coin but now he cannot go back there because he can't change the red belt direction.