I don't like how Samsung closed out the battery and microSD card slots for the S6 but I do like how it looks. I'm also a crazy person who does not put a case around it. I do put a case around my Samsung Note 4 Edge because that's my work phone and I tend to drop it more frequently both because of size and getting irate with someone at work.
Honestly, I could care less about the microSD slot. It does happen to be slower than a native flash chip for certain tasks like burst photos and I never fill up more than 16GB anyway (although I bought a 64GB S6 Edge because it was the only one available at the time). I take a lot of photos, I take some movies, and at most, I have maybe 4-5 hours of music for the times when I will be in an area with no data service. Otherwise, I just stream Pandora and call it a day. I have a 6GB plan. My parents are also on it plus my work phone, but it's basically 6GB by myself and I only use up maybe 2-3GB a month average. I'm sure the needs will increase over time but I don't have many downloaded apps because I try to keep a clean environment for all of my machines. I don't keep any full length video like TV shows in internal storage.
...I also do have a second phone that DOES have a microSD card slot. I may be cheating.
There's lower fidelity streaming that is not bandwidth intensive and Pandora is not nearly at 320kbps even in its HQ streaming.
I am pondering dabbling into a Windows 10 phone when such a thing comes out so I can see the unity of OS in the live on machines designed to take full advantage of Windows 10. I have an iPad for light browsing, an ipod touch, and APPL stock, but those are all legacy items for when iTunes was the only game in town before Amazon came to being for digital music/streaming services. I'd rather dispense with the Android/Chrome OS and sit on a single platform because I don't like the fragmentation of system knowledge just amongst my own devices.
But Microsoft has yet to win me their trust with Windows 10... which just crashed when I tried to sort my downloads by Tile rather than Details.