I have an enclosed deck that is basically worthless. It has a metal roof and bakes in the summer (and spring and fall for that matter) making it way too hot to use, and leaks in the winter (and retains no heat). I'd much rather convert it into an open deck. There are a few obstacles I have to get through first.
Edited to include only The first question here:
1 - While the pier is anchored in concrete, that concrete is below the level of the dirt. 
In this images the dirt around the pier is on top of concrete, however you can see the wet area where the dirt was and the the wood is beginning to rot. Will I need to replace this pier (and thus, all the rest) or can I pour concrete around it in a sonotube?