My day pack always has a basic FAK plus what I term a "core bag," plus possibly other items. I could easily spend a night out using the contents of the core bag - about three pounds of tastefully chosen goodies.
Though a little more substantial, you are describing my EDC. I designed mine when an unexpected overnighter in Dallas was the norm.
Jeanette Isabelle
I'll bet there are substantial differences. I would not be at all happy spending a night in Dallas> I grew up there and was happy to leave for wilder country.
Anyway, here's what is in the core bag:
bivvy sac (bivouac d'urgence, per label)
AA headlamp (Zebralite, variable level)
two candles, in small tins
Esbit stove
three Esbit tabs
Suunto mc-2 compass (w/mirror)
AAA light (Fenix LD01)
spare AA & AAA batteries (lithium)
whistle
match case w/ stormproof matches (25)
small roll duct tape
small bottle hand sanitizer (cleanser & fire starter)
Bic lighter
20' mason twine
DR Mk 5 knife (sharp)
signal mirror
wetfire tabs
aluminum container w/handle (cooking, water purification)
On a typical day hike, I will also have at least one water bottle w/ metal cup, TP, topo map, cell phone, AAA light, PS4 MT, wallet, FAK, full brim hat, bandanna, and appropriate clothing,including at least one lightweight jacket w/hood - maybe another MT or knife, depending. I take food and snacks, enough for at least one unanticipated meal.
I have delved into all this gear on at least two recent occasions, although not for an overnighter. I have spent the night out with much less, but I would not want to make that a habit.