Can iPad dim via idle timeout but not lock?

You can certainly turn off the lock code. The screen will still "lock" but it won't require any authentication to unlock.

If you're running a version of iPad OS that supports App Library, delete all but the two apps you want to see from the Home Screen. Yes, they will still be on the device but you won't have to look at them.

Unless the apps you're using can be set to require a passcode to make changes, I don't know how you're going to be able to have any kind of authentication. I just looked at Ring and it only seems to allow a passcode to access your account, not the app itself.

John Galloway wrote:

Thanks. If I select "turn passcode off" it says

Your apple Pay Cards and care keys will be removed Wallet and need to be manually readded to use them again. You will not be able to use this passcode to reset your apple ID password if you forget it'.

That sounds like this is NOT just relative to this iPad but my use of this code with apple services more broadly.

No, it's not. It means you won't be able to use Apple Pay on that device and that you will not be able to reset your Apple ID from that device. I agree the wording could be better.

I'm not worried about configuration/settings changes IN HomeKit or nest or ring, but for the iPad in general (and even that not so much since I'm the only one living here). I mostly want this so when I burn something and my nest alarm goes off I don't have to hunt for my phone to disable it but will always have something ready, so figured I could add HomeKit and ring as well. But that really needs an always on sort of mode.

Have you looked at Parental Controls?

Use parental controls on your child's iPhone, iPad, and iPod touch - Apple Support

There are lots of options and, I admit, I haven't spent a lot of time with them.

Even if the device is "locked" as in the screen is dark, it's still "on". All you should need to do is swipe. It's probably still faster than hunting for your phone.