Welcome to the forum and great first post.

Most of the others have already gave some good suggestions and your kit contents are very similar to mine for off-road /remote areas. The one thing I would recommend is another water bottle and also pen/pencil and small notebook.

We just returned from a weekend trip that took us over a 100 km (60 miles) from the nearest town (I'll do a separate post on this later.)

While traveling by vehicle or on foot, I keep extensive notes on weather, terrain, GPS coordinates of off road / trail crossings, (including elevation) etc in a small notebook and on the map(s). If we come by major creeks and rivers, I make note of the water, specifically if it is drinkable or not as right now with summer snow melt from the mountains, many of these waterways are so clogged with sediment that water filters will not last long at all. I also keep track of water usage, for example, I recorded 6 liters of drinkable water consumed on Saturday for 2 people.

In the event of injury or vehicle breakdown, having these notes could help in any number of methods if we are forced to wait for help (PLB equipped) or walk out.