Creating many small dungeons is no harder than one large one.
Yet, it becomes easier to link them into a series to form a plot. Some examples:
Urban Setting: A neighborhood of streets, sewers/tunnels, walls and rooftops, barracks/fort/prison, mansion/palace, ruined house, temple complex, graveyard/tombs
Mountains: A narrow pass, cave network, mines, dwarven settlement, remote stronghold/tower, magical site, ruined settlement, or dragon hoard. BTW, you can make up a dragon's hoard using my Dragon Name Generator, which does way more than name dragons!
Lowlands: A farm, a chateaux/manor, a mill, woodland, isolated hamlet/village, magical or religious site, shrine, burial sites, marshland, castle/fort
Coastal: Caves/tunnels, port/wharves, ship, tavern/chandlery, warehouse, tidal causeway, island, ruins/shipwreck, watchtower/lighthouse, markets
Sci-Fi: Decks or departments within a large ship/station, other vessels, planetary locations (see above), communal recreation areas, unofficial trading zones
Linking a series of dungeons does some of your plot-building work for you. While neatly dividing a story arc broadly into sessions.
It keeps the PCs on their toes and allows the DM to vary the challenges facing the players.
Populating each location with colorful characters and details from your world (Scabard connections) adds depth and engagement.
Hopefully you have plenty of ideas to build upon.
Check out Scabard's Connection Feature
Thanks,
-Stolph (Ed)