Long term safe storage

As my stash grows I have been looking into storage methods for long term hold. I don't think leaving at an exchange even with all the security settings in place and a sim swap lock on my phone is the answer. I have ordered a Trezor hardware wallet and was looking at the paper wallet from the Ravencoin website. I'm looking to sit on what I have mined for the next few years or it hits a price that I think is a good time to unload. All of these have their issues. What do you guys think?