Based on that alone, I'd say that you can update your OFW safely enough. 17.0.0 was a bit problematic firmware as it changed the way saves were handled, which rendered some of the consoles reboot to black screen, even those that never had CFW on them. Since you're already on it, 18.0.0 and 18.0.1 shouldn't be problematic. At least, as far as I know.
According to the developer of the Atmosphere, in version 1.7.0 the basic support for firmware 18.0.0 (and by extension, 18.0.1) was added and everything should work from the user side of things. Not all the modules have been updated to the latest changes and they'll probably address them in one of the future releases.
One should never update their console's firmware unless the latest Hekate, Atmosphere and sigpatches are released for that firmware. This is even more important for the people that are using CFW on their sysNAND. emuNAND? Not so much. If you have an emuNAND setup, I believe that you can update OFW as long as Hekate is updated to support the latest firmware, but I can't say for sure. Someone else can further clarify (or rectify) on this.
If you haven't done anything mentioned but not limited to what's written
here and you've been using your console's online features on OFW without issues so far (i.e. accessed eShop, bought and installed games, updates and DLC, played online games, etc.), I'd say that it
should be fine. Nothing's 100% sure, but I'd say that I'm around 99% sure that it's fine to update.
