Everything is up to date except not on the latest beta atmosphere because not recommended, and the latest 19.0+ fw I thought wasn't recommended,
I'm on the latest and greatest and yet to run into an issue. The more modules and homebrew apps you have on your current CFW setup, higher the chance that something might get broken after the update so take your pick. Firmware 19.0.0 introduced some issues with the unofficial GameCube adapters so keep that in mind. Also, forwarders stopped working and they need to be updated to reflect new changes. You can use
this tool to make your own forwarders if you want. Apparently, 19.0.1 fixed some of those issues but some unofficial adapters might need a firmware update from the manufacturer in order to work properly with the latest firmware.
I'm only playing game backups, not even using forwarders, cheats, overclocking, etc. Just playing backups. If that's all you do as well, I'd say it's safe to update right now. There aren't many games requiring the latest firmware in order to work, so there's that as well.
(I'm using 658 DBI as well)
It should fine for some basic stuff like installing NSPs and XCI. I personally use the latest Russian-only version.
TinWoo Installer is also an option if you want up-to-date English installer.
Not sure exactly what sys-patch is and how to implement that correctly, but I guess that's what upcoming atmosphere will be using? Is that compatible with Atmos 1.7.1?
For the end user, sys-patch does the same thing as sigpatches. I personally like it as it's easier to update and, since it has less files, you'll have less clutter on your SD card. For Atmosphere 1.7.1, I'd recommend using version
1.5.2 (I presonally used
this one, but both should work just fine). Atmosphere 1.8.0+ should use
1.5.4 instead.
oops
.