DJC wrote:I wish I knew.
The best levels to play are those that allow many different solutions, but how you plan this when designing a level I just don't know.
When your level includes gaining height, try to make sure the height is enough to make pulleys and rubber cost about the same - it's basically impossible for rockets to be the cheapest way! Also you can set it up so a see-saw is workable, which adds some experimental value!
Another way to 'spice up' the competition is to have some falling weights in the level, so the competitors have to decide whether to:
a) avoid/ignore them
b) use them as a counterweight for a pulley system or balance
c) Use them in a GPE launcher or see-saw
d) Incorporate them into the catcher
e) Make a new idea!
Basically, try to think of a few different ways you can beat your level, and test them out to see if one is obviously cheaper than the others - if it is, then adjust the level to make that way cheaper or the others costlier!