Anyone using some sort of skid plate on the bottom of their kayak?

Fished a local pond that used to be a quarry. It has one way in and one way out, which is a rough rock slope with multiple small drop-offs and humps. Used the Sidekick arms/wheels going in, but I felt like I would bend/break something trying to use them coming back out so I just drug it.

Also, any Native owners use something to protect the rudder in these situations?

I have a burley bumper bro on the front of my hobie. I’ve seen people mold them out of kydex. Thinking about making one for the keel. I’ve also heard of folks using the gator patches and gorilla tape but those will wear down eventually.

There's lots of options both to purchase and DIY. Search diy keel guard and you'll see those options. A lot of guys molding their own with a heat gun and some type of plastic/pvc material. I've done it with pvc but was never happy with the fit. I've always used Keel Eazy on my yaks with good success. That said I don't drag my kayak over rocks. Keel Eazy works fine for normal beaching but not much will work on rocks.

I use pereguard on my bow bc i like to come in hot a lot, and it's held up pretty good so far.

Kydex

I have seen a couple of yaks with aluminum strap Gooped or epoxied to the keel for dragging on concrete. Seems like a good idea, but I have no idea how it works out long- term.

I made a Kydex keel and use Keel Eazy on the rest. That's after alot of trial and error.
The Keel Eazy also doesn't slide real well on concrete.
The good, it doesn't fly down a steep embankment.
The bad, it also doesn't slide up easily the same embankment.
The trade off is worth it to me.