The Deus ex machina has never been to my taste, so I have chosen a theory of gravity which permits the existence of spiral galaxies without the need for dark matter (see previous post).
I have also been working out the fiddly details of how my choice of the elementary particle physics determines the stable and bound systems which can exist on medium length-scales. By adding an extra gauge field, the 'Monster' force field, I have obtained a chemical periodic table subtley different from our own. This, in turn, has changed the structures of the cellular systems which can exist in my universe. Whilst oxidation and reduction are the driving mechanisms behind the geochemistry and living metabolisms in our own universe, my own universe employs a more sophisticated biological geochemistry. As in our own universe, however, I will allow evolution by natural selection to generate the actual living species and ecosystems.
Calibrating my particle accelerator to produce exactly the type of universe I want to produce has been a challenging exercise. I am not, after all, a miracle worker. However, I think I have solved most of the remaining, niggling problems.
I plan to create my universe at midnight UTC tonight, on-budget and on-schedule.