In an Apple-centric forum like this, asking people to recommend or not recommend Apple stuff is like going into one of the political party forums and asking which political party is best. The vast majority of Apple people will endorse Apple stuff. I try my best to be centrist, meaning I'm sometimes praising Apple and sometimes panning them. I try to think consumer before the corporation. That said...
IMO, AppleTV is a fantastic streaming device. I use it every day and I consider it highly
underrated as a product, even by Apple Inc. themselves who still treat it like a hobby. In my home, they used to be occasional use devices typical of not-main-source-of-TV streamers, but then I added the
Channels App and and
SiliconDust HD Home Run boxes to basically turn them into TIVO DVR-like boxes for live television (free over the air and, optionally, cable via cablecard). That made it a
daily use device. You might want to look into both. It can turn your iDevices and Mac into additional live television sources too.
The various problems you (OP) describe will be overcome with the 128GB latest & greatest version. Many people don't fill up the 64GB version. You are getting by on an 8GB stick, so the latter is 8X more and the former is 16X more. Either seems well beyond your needs driven by working within the boundaries of the stick. The biggest space hogs are big games. If you are a gamer and you collect a lot of tvOS games, you could overrun 64GB.
One doesn't have to be invested in the Apple ecosystem to get good use out of AppleTV. As originally spun, it is an "iPod for your television" and you may remember that iPod worked well with Windows PCs too (and this does as well). However, your "bunch of Apple devices" does imply you are well invested, so this will make better use of all of that.
In general, apps are pretty polished on AppleTV. Since Apple regularly refreshes the box, apps generally have to keep up with tvOS, so they aren't allowed to get "too buggy" (though few are bug free).
While AppleTV is not subsidized by ads like the stick, Apple is not shy about working every possible angle to sell their own services and push their own offerings that require purchases or subscriptions. In other words, if you think you will escape streaming box marketing by going AppleTV, think again. However, Apple is not nearly as "in your face" about it as the stick.
HomePod can be irrelevant to AppleTV. HPs can be used with AppleTV but so can every other speaker in the world. My strongest recommendation is to link AppleTV to a Receiver that feeds "dumb" speakers in a true surround sound setup. However, many people link it to a simple soundbar for faux surround sound or faux ATMOS and some just use TV speakers.
- Vs. TV speakers, HPs will generally sound much better.
- Vs. soundbar can get into "ear of the beholder" territory (depending on the soundbar).
- Vs. true surround sound, HPs can't compete as stereo only (and there are ZERO rumors Apple aspires to grow that business into home theater surround sound competition).
As with ANY tech purchase, the most important thing is figuring out what you want to do with the thing you want to buy and then see if it does those things well. Make a list of apps and then check to see if those apps are available for AppleTV. I checked for the only one you named and there are Hallmark TV and Hallmark Movies Now apps for your wife. All of the big streamers are available for AppleTV too. But if you have some niche app you love on the stick, it may or may not be available for AppleTV... so you better check. Of course, nothing says both the stick you have and a new AppleTV can't co-exist.
As with all Apple things, they obsolete it in software every few years, so when you buy, you'll probably be replacing it in about 3-5 years much like iDevices. While pretty old ones can still function, the apps start "breaking" or app developers just outright stop supporting older devices no longer for sale.
Another con is that it's very much walled garden, so Apple must approve every app and many commonplace apps don't get through the gatekeepers. For example, a common want in any streaming box is some retro gaming/emulation. While there is plenty of horsepower to facilitate that, Apple wants us to buy/rebuy games vs. potentially being able to run games we already own and/or enjoy retro classics. Again, make a complete list of apps important to you and then check to see if those apps are all available on AppleTV.
Note that AppleTV the app and AppleTV the box are very different things... as different as iPhone the app (on iPhone) and iPhone the hardware device. Many people seem to get confused about what an AppleTV (box) can do for them since they already have the AppleTV app on their TV or other devices. The app is but a single app. Perhaps the best way to convey this is that the AppleTV app also exists on iDevices... but obviously iDevices do much more than only what one can do in that one app. Same here.
And lastly, I think one of the most overlooked AppleTV Apps is called "Computers" which is basically the one-stop-hub of all content you own. If you've ripped CDs into the Music app, Computers will offer up your music and playlists. If you've ripped BD or DVDs (or home movies), Computers will make all of those available. Your photo collection on your Mac is in Computers too. Etc. There are some other apps that get at some of that- especially via iCloud- but Computers can give you access to everything without paying a nickel for iCloud... IF you've got it on your own Mac or PC on the same network. Right behind the Channels app, Computers is my next most used app... and
then comes big streamers like Youtube, Netflix, Amazon, Disney, etc. Many people don't even realize what the Computers app does but I consider it a massive core benefit of AppleTV since I have digitized all of my owned media, making any of it immediately playable at any time.
I hope this is helpful.
