What a lovely thread! thanks for starting it Sekhmet and adding your old thread question to it.
I'm a keen composter and soil improver type of person. You will find great help at your local organic growers association; they will have climate appropriate worms varieties and knowledge on local conditions.
Like using blood and bone fertiliser directly onto the soil - the dogs recognise it as a food source, but if you add it to the composter and let it decompose you find that dogs no longer look for the food source; this way you'd also be able to kill off the guinea pig scent that your dogs would be after.
Its easy to ruin unwanted seeds in compost if you don't want them in there its about providing unsuitable seed storage conditions that encourage the seed to decompose.
What I sometimes do in my climate is "cook" the seeding grass or hay left overs in a tied off black plastic bag out in the full sun. The hay is soaked fully emerged in hot water for a few days and then goes in wet to the black plastic bag for a few days or a week, depending on temperature. I use the stand up black compost bins that you don't turn, you just add layers to the top. When full you leave it to mature, start another bin, and when its mature - lovely crumbly good smelling compost you just lift it up and spread the compost, moving the bin to another location to fertilise, the earthworms come up through the open bottom. Any herbivore manure is great and urine is very beneficial to the heap in several ways.
Sekhmet my Mom blends everything that goes into her compost in an old grinder. Everything. So yes you could find that a good solution for you too. This way my Mom's compost is extremely fine and matures super fast. She is on another continent to me and composts under different conditions.
There are as many essential beneficial bacteria's etc out there in air and soil; none of them can survive (good or bad) unless the host is an ideal environment for them, same as the potentially nasty ones... by keeping your own system alkaline and healthy you are granted a natural immunity by virtue of the fact they simply cant survive in your healthy state. Louis Pasteur stated at the end of his life: the germ is nothing the terrain is everything.