You can do pretty much everything anything in the oven you would do in the slow cooker. I appreciate what you say about gadgets, and certainly when my slow cooker was declared mortally wounded (a cracked inner pot), I declared that its replacement had to do more than merely slow cook. I ended up with an electric pressure cooker (a fast slow cooker really), which has multiple functions, including traditional slow cooking. I have never actually used the slow cooker function; preferring to use the pressure cook option, then leave on keep warm. I means a several hours casserole can be done in less than an hour, but kept long as long as required. Bone broth in waaaaaaaaaaaaaaay less than the usual 24 hour nonsense, and of course, it's a 8 or 8ltr capacity, which lends itself to batch cooking.
Smaller gadgets are cheaper to run than a larger oven, but obviously needs to be stored somewhere. Mine lives on a prep bench as it's used so often.
I'm an unashamed enthusiast.
