OK, my mother always said "if you can't say anything nice ..." but you are asking for opinions and I think you deserve to understand why I might not be back as a fan.
To me, the cheating you're doing in this story is fine, it's your story, that's the way you play the game, and you are up front about it. Where I think your Dynasty crosses my line is creating all the spouses in CAS. Not only are you depriving your readers the joy and intrigue of watching the story progression future spouses grow up and get to know your family, but you're denying yourself the fun and delight of discovering the future spouses story progression creates. I think you will be missing out on so much of what makes TS3 so interesting and awesome. Blue babies are great but are they worth it? I'll throw out the idea of creating a number of blue male and female Sims and putting them into your town, that way the potential for blue babies is there but it's less controlled.
That's my opinion. I don't mean to offend.
