Gun Safe - Surface Rust

All I can add is that I have "damp-rid" packages in my safe, and some of the blued steel guns STILL rust if I touch them (even briefly) with my bare hands, even just to move them out of the way to grab something else behind them.
I really should have a cheap pair of cotton work gloves to slip on when reaching into the gun safe.

I don't oil my guns heavily. Just a casual wipe-down with a cleaning rag that has a bit of gun oil on it.

Maybe I should oil them more. But I don't like what excessive oil does to the wood, and it's hard NOT to get gun oil on the wood stocks.

Haven't seen it mentioned yet but I may have missed it. Get a dehumidifier!

A few years ago we lived in a house where the only space available to store my guns and reloading gear was in a room attached to the garage. There was no climate control and here it gets extremely humid at certain times of the year. We came back from vacation one weekend and I went out to the garage only to find that almost all my blued rifles had orange dust on them. Luckily it came off almost everything but I had a dehumidifier on order that day.

There are several good ones but I ordered the one with best reviews on Amazon. It is rated to pull up to 70pt of moisture a day and I emptied it twice in 24 hours the first day it ran. Still have it 5 years later and it runs great and I have had 0 issues with moisture or rust since.

Get the safe in a climate controlled room. If the heated rods aren't handling the dampness I might suggest run a ceramic light fixture like this https://www.homedepot.com/p/GE-Medium-Base-Keyless-White-Porcelain-Lampholder-18304/203716800

I put something smaller which I couldn't find in a couple of mine. I attach it on the inside of the safe. I leave it plugged in all the time but if it's real damp and high humidity I'll put a 40W old style light bulb in it and leave it on 24/7. When I didn't need it I'd just unscrew the bulb some until it went out. If I needed it again I just screw it back in. When I lived in FL I kept a gun safe in my garage and that's what I did. The bulb and a Golden rod and I never had a rust issue no matter what the weather was like. It would be hot all summer and cold in the winter.
I also swear by RIG . I apply it with a sheepskin wipe and been doing that for probably close to 45yrs. Handguns I wipe down with RIG then put them in a 1 gal Freezer bag.

I should have mentioned having a barrier between the concrete floor and the bottom of the safe. Even a rubber mat if you can find one big enough serves the purpose. Don't use cardboard because it will absorb the moisture. Even a plastic table cloth would probably work fine especially with several layers folded up.