actually, what you need to get a good character is...
raise the weight, there are certain weights for certain creature
like for example to get a Koganetchi you have to raise the weight til 40
if you want a mushibatchi you have to raise the weight til 60
how much is the weight of your mori when it turns into a cacoon?
You know I had the same problem and I read the end parts of Kat's morino log and she got the same results with your advice. I'm definitely going to have to try that sometime

Do you know the exact weights to go for to get other characters?
if you want a Funkorogatchi (which im sure nobody wants it)
you must make the weight as low as possible! or as high as possible
but there is a big chance you will get a Mushibatchi with the weight 60++
You have to get 40 to get a Tentotchi too, but dont forget to lower the temparature or you will get a Koganetchi
I dunno how to get a Futagoaoritchi, but there's some people emailing me from my website, claiming that they have a secret characeter, I kept asking him/her how she/he got it, but they never replied...