For a similar price to the top spec Eggbeaters, you could buy an SPD-compatible, dual-sided pedal power meter. For many gravel bikers, the terrain is more likely to limit their progress than their power output, but if you're into gravel racing, a power meter can be a useful addition to gauge your effort level. It's also really useful for training to assess your fitness level. Metrics such as pedalling smoothness and platform offset can also help you improve your efficiency.
Gravel bike pedal power meters are built robust, so they should be able to withstand grotty conditions and the occasional rock bash, but in a serious wipe-out, pedals tend to hit the ground first, so you need to be happy with the risk of destroying a pricey power meter and the cost involved in replacing it. Fortunately, you can buy spares for all the power meters above.