Single stacks need to get a lot thinner. Why? Because the P365 is as thin as most single stacks. The P365 is as thin as the most famous single stack the Kahr PM9. The P365 is overall smaller than the APX/Nano. It's also lighter. So unless you are price shopping, feature wise the P365 wins.
Those single stacks that are thinner tend to be bigger overall (PF-9/LC9). The LC9 single stack is overall bigger than the P365 except for width.
Smallest single stack being junk (DB9) is the same size as my LCP. Exact same size. But it's junk. If a 9mm could function in an LCP size, sure. Single stacks live on. Otherwise? I don't think so. Single stacks outside of the PM9/PF-9 are really new. They don't have to live on. Since Taurus dumped it's Diamondback partnership with the DB9, I don't think an LCP 9mm is going to happen soon. Even the Remington RM380 which is a copy of the Roughbor R9 is almost the same size as the P365.
So for small current 9mms, the P365 is currently the winner. Happens to also be a double stack. Also happens to 100% functional. That's a problem for single stack guns right now. I don't believe 10 is always better than 6/7...but I don't think it makes since to have 6/7 and be larger. When was the last time you heard someone buy the best since stack (PPS M2)? I haven't in ages. Will people buy an LC9 at $200 bucks (like they were being closed out for last year)? Yes.
But, time to trim the width.
Also, the market for my P365 at a better loss price for me is probably a bigilion times larger than any single stack. That probably will only become more true.
First of all, Single stacks are not going anywhere.The 365 may have been a winner for yourself, not for all others. Certainly not for myself. (But I respect your personal choice and the 365 is a very nice gun) There is more to a EDC gun than just a few more rounds. Control, handling, etc. I can shoot the Nano much better than a 365, much less recoil and it is SMALL. Yes a few ounces heavier but it is almost over built. A very solid firearm that will outlive me for sure.
No the Sig 365 is NOT smaller than the Nano. And the gun is thin. Actually the Nano is thinner than the 365, shorter length. Yes it weight 2 ozs more but the is much easier to control and none of the snappy shooting.
https://www.handgunhero.com/compare/beretta-nano-vs-sig-sauer-p365
The gun behind the LCP is a Beretta Nano
Modular design is so easy to work on. All stainless steel.
I also love the amount of real-estate on the Nano vs the 365 for the Offhand grip. And I like the sleeker design.
<a href="https://imgur.com/iBs9Onl"><img src="https://i.imgur.com/iBs9Onl.jpg?2" title="source: imgur.com" /></a>
Also you can see the beefed up design of the Nano
The Nano also comes with some of the nice Stainless Steel mags I have seen. Much like custom 1911's. Metal follower.
Getting back to the OP. do not forget that You will also be giving up the great DAO trigger (striker fired DAO). Much like the Kahr which many love. If you like the other Triggers that is fine.
PS I am no way disparaging the 365, hellcat etc. Great guns, All pistols have their pros and cons. I prefer the single stacks for various reasons, If some one else prefers a Double stack that is Fine with me.