Under older Android OSes, I could choose to put working files for my various apps on the SD card rather than on the main phone memory. Since I work with large files (typically pdf files, which could be engineering drawings, aerial photographs, etc.) that I edit in the field (meaning duplication of files to accommodate the edits), I use up memory quickly.
As for 4.2 being a better system for me than 4.4, I just find the newer OS to be more complicated, less user-friendly and more difficult to do simple tasks. Others will, of course, disagree for their own uses, which is fine. Th problem is that Verizon decides what OS I am to use rather than allowing me to make that decision for myself. It's as though Sony (my laptop maker) were to decide I could no longer use Windows 7 and forced me to accept Win8.