Is running 'opkg upgrade' for all of my 'list-upgradable' applications a good or bad idea? I don't have any issues, so I'm inclined to leave them alone. BUT, I am running LEDE over OpenWRT for no reason other than "it's newer, so it's better", lol.
In general it is a bad idea.
Or at least you need to be careful that you only upgrade kernel-independent userspace apps.
One major reason to NOT upgrade is flash space. If you try to upgrade any apps already included in the flashed firmware, the original copy is not deleted but a new one is added, and that will consume disk space.
You might use that list to selectively upgrade some apps that you have installed by yourself. But a mass-upgrade is not wise.
In addition to hnyman the space issue depends on the device. On my Netgear X4S I have 19MB available for updates. Since the original filesystem is only 4MB in size I can run updates all day long and never run out of space.
I exclude "base-files" and any package that mentions "Multiple packages".
Now you can add "libubox" to the "Must Exclude From opkg upgrade" list. It's much more disastrous than upgrading "base-files". At least one can get out of it from failsafe mode, after upgrading the latter.
See my new thread: Bricked, due to "Error relocating /bin/ubus: uloop_run: symbol not found"
Recently I just crashed my router by upgrading all the packages xD
I wouldn't recommend it...