From your your details it is clear that you are already familiar with Electrum wallet which is high usable wallet for Btc . Actually Electrum wallet is beneficial for those who need daily spending of BTC. As you alread mentioned that you want to hold BTC for long time so I will recommend hard wallet to store BTC. Any cold wallet is not safe for storing long term.
Ledger is best option for you to store which is full secure and no risk at all to store for long term. Trezor is also best one as mentioned by Kiakia. I am using Safepal Hardwallet to store my coins and I think it's also secure to store BTC. You can use any of Hardwallet according to your need .