You should really cast some other people.
OK, this a general review of all your FG flashes. The animation is great, the script's are OK but timing and voices need work. For timing, the space in between lines is too long and isn't necessarily funny. Also I think you should release an episode in no more than 2 parts. Your Peter is very good but to be frank the others aren't. Brian is totally wrong, he sounds too young. As for Stewie, that's about a 6/10 cos the voice is nearly there but the performance doesn't bring out the character. His eccentricities in no way come across. In an earlier flash, Quagmire and Brain sound almost the same. I respect you for doing all this, but you should really cast some VAs in roles other than Peter. (PM me and I'll point you in the right direction.)