To be honest, there's nothing like "the most secure" btc wallet since there are always ways to bypass any security measure.
I personally always have a hardware(offline) and a software(online) wallet. If one gets hacked, the other one will still have some btc left.
For the Online wallet, I'm using Blockchain too, since I had a great customer support experience there.
For the Offline wallet, I got a Ledger Nano S for 20$ from a scammer who probably tried to do the "recovery scam" since he gave me his credentials instead of factory reset the wallet.
If you want to protect yourself against those Ledger scammers, watch this video that explains everything about this scam :P
This video helped me to save quite a lot of money by finding one of those scammers and basically making them loose money by doing a factory reset on this wallet