Catalytic converters seem to be a hot commodity these days, you may want to secure it first. There are also products to change the locks on external compartments because the keys are so common, and some people secure their generator if that compartment is not locked. As for the interior, the best security is to park it around other people and leave the shades up so everyone can see inside when you're not there. From there you could add the various security items you mentioned, and I think your approach is correct if your unit is worth it. Half a dozen small cameras should easily cover the interior and exterior, and an app will give you live notifications as well as full-time recording. This will be easy if you're plugged into shore power and have constant Wi-Fi, but could likely be possible otherwise as well. Let us know what options you go with so that we can also benefit from your research. Thanks for the topic.