Here’s the bike itself and everything permenantly attached:
Here’s what I attach and remove every time I ride:
Here’s what’s in my trunk bag that I take pretty much everywhere and I keep room to add the detachable stuff and clothing depending on weather:
I normally don’t take a lock with me because I just don’t need it.
Having a single “trunk” pack that I just have to open and load up and take with me (has an arm sling) is by far the easiest way to deal with stuff. I hated having to attach and unattach a noisy handlebar bag every time (but sometimes do if I need more storage). On longer trips I can through the Ortlieb panniers on the back as well and get pretty much all the storage I could ever need. The twist ties hold down helmets and whatever in the fastest way possible and double to hold the front wheel in place when on the rack. They also hold the U-Lock in place (on top of the trunk bag) when I take that with me.