Quick turn around product have some huge advantages for small businesses as money is not tied up,for months waiting for product to be ready , but they also usually mean that the product goes bad quicker too. So a business needs to start off slow and build the demand so product is not being wasted and costing the business too much money .
Usually with handmade edibles like bread or cheese or others like this , it is best to prove out a production model one that takes 1 to 3 people then when demand picks up to not go out and buy machinery to increase production but to add more people trained to run their own production models , this is a good way to keep costs low , increase jobs for all and most importantly not to decrease quality of the product that has driven customers to desire the product in the first place.
Kefir might be a better product than yogurt as it does not need cooking thus it lowers costs , but yogurt is an easier sell as more people understand it , at least over here . Yogurt and kefir will also need containers of some kind and they will need to be purchase in some kind of volume to keep costs down .
Fresh mozzarella would be a really good money maker if sold to higher end pizza restaurants bu the making Mozzerella is going to take a little time and some wasted product as the ph is really criticle , if they could find a teacher then that would save much time and money .
Soft cheese could be done in as little as 6 to 8 weeks but would involve affinage / aging , this involves storage and all,the cost associated with that . Plus spoilage for cheeses that do not get sold.
As you can see there is no easy answer and each ideas comes with good and bad , some issues can be solved creatively and thus become advantages others can not. Usually the best way to make money in a business is to to,spend it in the first place. In other words keep costs low.