The non-removable battery is simply limiting a feature that otherwise could prove useful to many people.
I do not work at a traditional office. Instead I work at client sites, and travel from location to location. I am not a cubicle worker that has the luxury to plug in my phone all day. If that were the case, then I wouldn't care if the battery only lasted 30 minutes, because it would be on the charger all day.
The lack of removable / replaceable battery is a major deal for some people, like myself, even though I have a plethra of car chargers.
Same thing with the microSD card. I forgot to mention another major benefit of the microSD card.
When I used the HTC Evo 3D, in stock form, I experienced a black screen of death. Only a factory reset would bring the phone back to life. Unfortunately I had used the internal storage to store some photos / videos, and after the reset, all of that media was wiped out. Had I stored it on external SD card, that information would still be recoverable by simply pulling out the SD card and reading it on a different device / PC.
By not having an external storage, you place your valuable photos and media at the mercy of the Gods, should your phone get some serious damage that requires a factory reset, or is non-functional at all (dropped in water, bricked, etc...). External SD cards at least offer you a chance at saving your data in these scenarios.
This major benefit plus all the other numerous benefits mentioned above should sway most reasonable people as to why SD card support is important, and removable battery too.
The S3 is pretty slim, does not sacrifice form factor to have a removable battery or SD card. So why should Android users have to suffer and be limited in their choices?
There is NO proof that non-removable battery / lack of SD card provides any compelling benefits on Android, especially if a user doesn't care if the option is there or not. In these cases, then why defend the limitations to those who want a removable battery or SD card support? I can't understand that.