28 weeks in, and you've only covered religion as it relates to other things and in a very sideways fashion, so far. =)
Inheritance laws: Do they differ between classes or castes? Are they set in stone or fluid? How do they work and what happens if there's no one suitable to inherit, or there's a serious objection to who would inherit normally?
Taxes: Do people pay taxes, or do they pay their governing structure in some other way? If they don't, what are the ramifications? If they don't have someone to pay or don't need to pay in some manner, who takes care of the common areas and enforces order?
Decoration: Personal decoration, decoration of home and personal belongings, and decoration of public buildings. What are the fashions and adornments like? Do they change often? Is there any meaning to them?
Industry: What are the big industries? Why are they profitable? What resources do they use, and what sort of impact do they have on the land and people? What measures are taken to protect farmland, water supplies, people and animals from the resulting pollution? Are there any laws/rules about where the structures for these industries can and cannot be located?
Ecology: What crops are grown, what fruits, what plants for industry and trade? What plants have been around for ages, which ones were recently imported, which ones have to be carefully cultivated in special conditions? What raw materials are used from the area? Do your people have rock quarries and mines for metal? How much forest is available? What, if anything, governs the use of those resources? And how do the people get around those when it's inconvenient?
One more. Stimulants, depressants, and other such drugs. What sort of drugs are in your world? What drugs are viewed as commonplace (caffeine in coffee and tea, alcohol, pain medications) and what are the more illicit ones like? What are the societal views and laws on them like?
Childrearing: who does it, why, what does pregnancy/gestation entail, what's appropriate or not appropriate for children, what status do children/child-rearing have, what constitutes a crim in relation to children?
Households: what makes one?
Family structure: Who's in charge? Why? What are the relationships to one another? What's the line of descent? Who is considered related to whom?
Sex and sexuality: what's normal? What's accepted? What's criminal? What's deviant-but-not-illegal? What's not illegal but will get you run out of town/beaten to death? How does gender relate to biological sex and to sexuality? What stereotypes and assumptions exist?
Oh, and somewhat duh-like - crime and punishment. What's a crime? What kind of legal system is in place? What's its basis? for instance, British-descended law-systems have something called "common law", which actually originally meant "this is so self explanatory that pretty much everyone agrees this is Bad or Wrong"; nobody was going to say that murder wasn't a crime, so the "common law" (ie: law that was common to everyone) punished you if you killed someone without justification. In contrast, many Islamic countries have their sharia law, and for a very long time European countries had "canon law" running right side-by-side with the "common law", and while canon law dealt with things theological/religious and common law with things secular, both were very real law courts, deciding everything from inheritence to prison sentences to death.
What are punishments? What's considered a fit punishment to what kind of crime? What philosophy governs punishment? Again, for example, most mediaeval punishments were equally focused on punishing the offender, warning other people what would come, and warning other people that this person had offended ("pillorying", which we now use as a media attack term, originally meant having your earlobe nailed to a block of wood in the center of town; it hurt, you were humiliated, everyone saw you, and then when your term of punishment was done they just ripped you off the nail, which meant you were then marked for LIFE as someone who had been pilloried, due to the scarring). What is society's attitude towards criminals? Where are they kept, assuming they're kept?
Etc. :D Considering my chosen eventual profession, I probably should have thought of this sooner, but.