A lot of these things I hadn't even thought of since I tend not to really map out my settlements (at least not in minute detail) it means that if I need a park in the city due to an adventure or PC query then I can add one. Still, of the things I do think about, mine tend to have a central stronghold around which the rest of the city is built. A river as main water source, guilds, city watch and walls, a magical academy if some sort (the city I'm thinking of has Draconis Sorcere, a guild/academy which draconic sorcerers can join), underground sewer/water ways, a harbour (in this case the city is built around a large lake), magic shops which have mostly uncommon items and consumables (but they might be able to find someone willing to sell other items), and a large trade centre (several actually). Their library is also the temple to the Sage since this god deems that knowledge should be used by all the temples tend to have large libraries and keep historical documents for all to peruse. This is one of the largest cities in my world having been the seat of draconic power back in the mythic age it has retained much of its majesty and influence.