Well, not so much drama, the update nag screen on my S5 was becoming annoying so I figured it was time. Uninstalled apps that I had added, wiped the cache partition and did a factory data reset. Installed the updates and bam, it's done. Well, almost. Put some stuff back in and things seem to work pretty well. Not particularly better than before but it works so that's a plus. No lag and I'm not noticing heat issues. The colors, UGH. Some of my apps are now reinstalled. Data, WiFi, calendar, contacts, Google account, calls in and out, text in and out and event sounds all work.
For data control I turned off data, checked "restrict background data"and in the Playstore app checked update apps over WiFi only as in Kit Kat. Only difference is that there is now a fairly large nag that keeps popping up regarding my having restricted background data. Gotta be careful as accidentally touching the darn thing will likely undo that setting. For data limiting, having only a 1 GB plan, I set the data max limit a 900 MB. I've found twice already the setting has mysteriously reset itself to 5 GB. Pretty good payday for someone. Just saying. Keeping my eye on that.