Needing to add a little off-highway capability

There is such a thing as a hybrid RAV4.

Sometimes it is cheaper to pay to improve the road instead- the results work with all cars. I'm not suggesting that should be your next move, but just something to keep in mind when these other ideas go swirling around.

 

If you're due for new tires, look at getting a size or two larger.
The OEM size for a 2005 would be 185/65/15 but many people use a 195/65/15, which moves the diameter from ~24.5" to ~25.0", providing an extra 1/4" of clearance. A 185/70/15 gives about 25.1" diameter.
I think you may even be able do 195/70/15 which bumps it to ~25.75" which would give about 5/8" extra clearance, but you may want to verify no rubbing in the front wheel wells at full lock..

I seem to remember the 185/65 OEM tire has the car read one or two mph high at a true 65mph. Going to the 195/65 makes the speedo dead on at 65 mph.

Buy a good all season or off-roadish tire in those sizes and kill two birds with one stone. MPG will likely drop a little, but some of that drop will just be from lower mph indication and some will be from a tire that's less focused on MPG.

 

And 2 mph increase in regards to 65 mph also means that you'll travel a longer distance than what the odometer will state. Over the 100,000 mile battery warranty, that's an extra 3,000 miles of "free extended warranty"

 

Taller tires will very definitely reduced the 'apparent' or 'displayed' MPG, due to the altered odometer calibration, so you will need to adjust for that. If the accompanying speedometer shift also causes you to drive faster, then note that the higher speed also reduces MPG.

These are phantom losses, in addition to any real MPG loss from more aggressive tires.

+1 separately each for the RAV4 Hybrid or Prime (I recently traded in my Prius for the later), and for 'improving the road'.

After widower-ed dad traded my late mother's old sedan for a used Jeep, then my car (first an old Accord, later a 2010 Prius) became the only remaining low-clearance car frequently using his road, so I became the one regularly knocking down the grass and scraping some of the gravel building up as a center hump. All the other extended family's vehicles were F250s or SUVs, so after visiting only in a Subaru during winter, my first Spring visit in my regular-clearance car would be worse.

This ended after I discovered that he had acquired an antique box grader, salvaged by a friend years earlier, but never used it. This is a road maintenance tool dragged behind a tractor, older and more primitive than this modern sample, but still reasonably effective. So I began using it and maintaining his road, annually knocking down the growing center hump and filling in the tire ruts, greatly reducing erosion, mud, and gravel loss during the spring thaw runoff. This was something dad never meaningfully attempted to control, instead just lazily ignoring it until the road was terrible, then having the local gravel pit bring out and spread $everal truckload$ of fre$h gravel, half of which would disappear the next spring.

This tractor-powered scraping and grading process does have a learning curve, but eliminated the car center dragging, and greatly reduced the need for replacement gravel. The last contractor to re-gravel and re-build the road gave excellent road maintenance advice, and fortunately I was present to hear it. It just went in one of dad's ears and out the other, but I payed attention and learned a lot from him.

 

What do you mean? He said there is such a thing here:

... and you even replied to that earlier here:

 

It's pretty early in Colorado, so I'll guess somebody found the keyboard before the coffeemaker.

Understood. I only mentioned it because some people don't realize it is even a possibility, and I can't see your road from here.

There's a rough four mile dirt road leading to someplace I care about. The community pays to get a real grader up and down the road twice a year, but they also bought a small box grader. Certain members of the community drag it from one end to the other behind their pickups, and we've arranged storage for it at each end. Makes a big difference in the months between the pro sweeps.