I have exactly the same thought, and exactly the same setup. It’s been serving me well, why risk fucking myself up with more complexity? 

 Keep it stupid simple, you guys are good 

 CC and sparrow too. Made my own seed using dice.  I feel plenty secure 

 I’ve talked to experienced devs who use single sig or single sig and a pass phrase. 

The trade offs for multi sig don’t really make sense in my opinion. A lot of added complexity, more expensive to set up, harder to maintain, harder to access in an emergency. Yes, it’s more secure. But the security offered by single sig is absolutely sufficient. 

Metaphorically, the castle walls are already 10,000 kilometers high. Why make them 20,000? 

 Good analogy 

Do I really need to add a crocs to my castle moat that already has crocs and a draw bridge? 

 That already has gators 🤓 

 Don’t forget the frickin’ lasers 

 The drawback of "harder to access in an emergency" quickly turns into a feature if the emergency is duress. 
Sure you can do a honeypot wallet with another 25th word, but that does not work as soon as the attacker knows one address of yours and becomes suspicious why it does not show up on the wallet you unlocked for him. 
With MultiSig it is evident you need to gather several keys and might have to travel places dkr that ... 

 To avoid single point of failure.