I have yet to get a rare bug in one of my families. In the other I have 7 bugs, two of which are rare. The family that still has only two total bugs was started prior to the .05 update. The other was started after. In the family with 2 bugs, using the tropical rain only seems to give me coins or the millipede/catapillar. In the other, I have had at least one new bug show each time I used the tropical rain.

I spend twice as much time with the family with 2 bugs than I ever have with the other, and have completed all of the collecting trophies except the bug collection and the two trophies that depend on finishing that collection (the completing all four collections and getting all the collection trophies)

In that second family, I have 11 coins, 3 picture pieces, 5 nuts and twigs and 7 bugs. My husband has also noticed bugs appearing more frequently with his two families that were started after the .05 update. If I weren't so attached to that first family, I would delete and start all over.