I posted some initial thoughts here:
And now after a week or so of ownership and approx ten flights, and after having just read the instruction manual, here’s some second thoughts 
In no particular order…
The RTH height resets to 15m on every boot (PITA) yet the Max Alt and Max Distance values persist (PITA):
The broadcasting of all your data to the world resets on every boot (#FAIL)
It appears that you can cache maps. Initially I didn’t think you could, but this evening I spent some time panning and zooming all over my local area while the drone was powered up and connected. I then shut everything down and force-closed the app. Then switched to airplane mode and fired everything up again. I could still pan and zoom to my local area that I had cached. Zoomed waayyyyy out here, but it let me zoom right in no probs:
The number of sats displaying in red / white is very inconsistent.
Here we have 11 sats locked on, yet still showing red, with a caution:
Now I have 8 sats locked on, yet good to go apparently 
Is that important? See this thread.
There is NO option to unlock NFZ areas on the map. And if you go to DJI FlySafe you’ll see the Mini is not even listed 
It could come in the future I guess, but for now, you’re NOT taking off in those blue zones 
A few quickshot modes exist, sadly a 360° pano is not one of them 
The cable that connects the remote to the phone is very thin and flimsy looking. I worry for it’s longevity. To the point where this evening I just ordered one of these as a just-in-case:
https://www.amazon.co.uk/gp/product/B071G5PGGT/
The batteries discharge after 10 days. There is no option to change this. Wasn’t this the case with the Mavic 2 on launch too? 
Did they ever put an option in the GO4 app to change that?
Having now read the manual, flying in temperatures between -5C to +5C it’s recommend to hover for a while after take off to warm the battery up a bit.
The remote controller has a battery capacity of 2600 mAh and a maximum run time of 4.5 hours when using an iOS device.
Android fans, cover your eyes 
You guys can expect your Mavic Mini remote battery to only last 1 hour and 40 minutes 
I’m guessing this is due to the way Android devices handle USB charging?
Either way, it’s one thing us Apple fanbois actually have over you guys, so I’m gonna milk that right here and now.
1hr 40mins
Moving on…
As there is no physical sport mode switch on the side of the RC, you can press the RTH button once to cancel quick shots. Is this the case on the Mavic Air or Spark? I’m guessing you could also use this to exit Litchi missions in the future?
Not sure if the Mini has Precision Landing? I only tried RTH once but didn’t pay much attention to where it actually landed. Has anyone tested PL properly?
The manual recommends calibrating the compass if you’re more than 31 miles from your last flight, or if it’s been over 30 days since your last flight. WTF is that all about?
I’ll try another update in a month or so after more “real world” use.
At this stage, would I recommend the Mini?
It’s actually pretty good, especially considering it’s size.
It struggles in the wind, and it struggles with WiFi interference. If these are likely to affect you, I’d probably not recommend it.
If those two factors are not an issue, then sure, why not? Especially as a first drone, it could be ideal.
The major down side for me as an ‘advanced hobbyist’ is the simplicity and lack of features / control within the DJI Fly app (and a lack of RAW photos). But we knew that already, right?