A lot of people are very confused on the SD card changes. YOU DO NOT LOSE SD CARD access! The change was that if an app created a folder on your SD card to store stuff, another app cannot access and make changes to it (Which is how it should have been from the beginning). There are many reasons as to why this is the better way (many security related as well as programming related scenarios).
This means that each app can create and write changes to SD card folders it creates and no other folder. The app has to be the creator of the folder it's making changes to.. that makes sense right?! You can still put all the music and pictures and documents you want on the SD card and they will still work like in the past. A few apps had to be updated because they were doing things the old way, but that's been done and you shouldn't have any issues that people had when the change first was done.
4.4 adds a host of new features, bug fixes, network efficiency enhancements and security patches (some are very serious and if you're still on 4.3, your phone is at risk daily). I highly suggest everyone upgrade. If you have any particular issue, private message me and I will help you address it!