I've directly shared your post into PW for their take and to see if they can find those bug reports.
I have not personally had issues with any of that (except the stuttering...) on my personal switch or my devkit and nor have my kids. That said, this just means it is not universal and there is some trigger here that we need to identify.
For this "crash location", can you provide any details on it? A screenshot or even a zoomed in map shot? Sometimes its crazy stuff that causes these things (looks at the firefly crash from mobile back in the days)....
I just checked my kit and I was able to Reforge and use the Guide Crafting Interface fine. What precisely is occurring?
What are the reproduction steps for this item deletion issue? I have not had that happen to me on either of my switches... but maybe I am not doing the exact things to have it happen. Obviously that is serious.
Stuttering is known to PW, that much I can 100% promise you. We bring it up as well.
All I can promise is that 100% will make sure this is seen and see what's up.
The deletion bug seems to only affect me when using the touchscreen. Especially when swapping around inventory items with the upper inventory items (or perhaps swapping any items). I have auto-pause enabled if that's any reason. So far using physical buttons I haven't experienced this glitch.