Finally getting around to working on the bathroom. Lots of lessons learned so far, and will sum them up in the end for the other DIYers. As I am familiar, little mistakes have huge trickle down ramifications.
The existing 80s construction was strange, not sure if that is how they did it back then or this was a unique case. The existing tub surround was regular drywall (not even green board) with another layer of drywall over that. The tile was then put on like a countertop with a large bullnose over the extra layer of drywall. No moisture barrier anywhere. However, the tile was very precise. There was not a bit of moisture anywhere. It made pulling the old tile off very easy because the whole tiled wall came down in one piece. Unfortunately because of this I did not think of certain things.
1) Lesson 1: CHECK YOUR STUDS AND SHIM OR PLANE TO LEVEL THEM. So I assumed since there was existing tile the wall was flat. So I cut out the existing wallboard and put in CBU. Taped and filled in the joints. Only then is when I ran a level across the wall. It was horrifying. The stud along the shower valve must have been bowed out about midway down so the wall was bowed both vertically and horizontally. In fact all the walls had some bow in them. I wanted to cry because 10 minutes with a hand plane and shims would have solved this. Now it was either too late or required cutting the CBU out. I could not bring myself to cutting it back out, so I tried to float some thinset in the low areas and actually came out OK. However, the trickle down effect is causing problems as I lay tile. This fact is not emphasized enough, also finding wall shims is not easy
2) Lesson 2: LEAVE SUFFICIENT TRANSITION FROM CBU TO WALLBOARD. I do not know what I was thinking, but I guess I was thinking the more CBU the better. Lesson 1 compounded this lesson. I put my transition right to the end of my tile, I think I should have left at least a full tile length. My CBU was lower than my wallboard, but I thought I could make this up by feathering out the taped seem. Unfortunately by the time I taped it, I raised the transition even more. So there is a hump right at where my tile ends. I am going to have to play with my bullnose to cant it by a 16th, or have a pretty significant caulk line.
3) Lesson 3: FOR WALL TILE MIX THE THINSET THICK. I did not mix my thinset on the thick side and it was difficult to work with. A lot of mess and bleed through that needed to be cleaned up. It still trowled up, but was on the thin side. Next batch with be thicker.
4) Lesson 4: I had a bag of the standard 1/16th rubber QEP T spacers. I could not get these to work. Every time I adjusted a tile or tried to set it level they would pop out. If I brushed the tiles they would pop out. I tried the plastic TAVY spacers and they worked so much better. For the DIYER I recommend those.
5) Lesson 5: I watched a lot of videos where they lay multiple rows of subway tiles by basically building a pyramid. That way you can lay tiles without stopping to do your cuts. Then once you have multiple rows done you can fill in the cuts tiles. The problem with that is there is no way to check your level. I found for a DIYER it may be easier to simply mark up 2 or three rows and draw a level line. Then do 2 or three rows and run a level. Then you can use your wedges to adjust. Anymore than two or three rows get challenging to adjust.
6) Lesson 6: Wife wanted the subway tiles, not really my thing. So I wanted to at least get 4X8 subways. I found this really difficult to do. I am in a big metro area with lots of big box stores and tile warehouse stores. I see them everywhere in magazines, but could not find them. Finally went to a local distributor (new favorite store) and got them. Pretty pricey compared to the big boxes.
So now for some questions.
1) Because of lesson 1 and 2, I decided to lay the last field tile and not the bullnose. I was considering to lay all the field tile and do the bullnose at the end. I need to be a little careful to cant the bullnose to get it to lay flat against the wall. I am guessing I have to cant it a 1/16th. Here is an image

Is it ok to do it this way, laying all the field tiles and finishing with the bullnose? Or am I likely to mess this up? Should I mark the line for the bull nose and work in from there? Or does it matter?
2) I am planning to do a ceramic shelf, and cannot find a good tutorial. I have seen some tutorials for flat marble shelfs. Do I put simply notch the row above and leave the row below full? Or notch the row below and leav the row above full. Any link to a tutorial or thread:

3) I am still planning to do the floor in 2 inch hex marble tile, and would like to do a border in the shower:

The border is about 1/16th thicker. Can I leave it a little proud? I think it would look interesting especially with a lot of 3D tiles you see now, but afraid people may just think it is sloppy. Any opinions on that? If not I would do pencil tiles on top and bottom. Man those pencils are expensive. The room is supposed to be classic/modern with modern fixtures but the classic white subway and white marble. So I was thinking without the pencils would look more modern less formal.
So I ran a level across and I am definitely getting off level. So I plan to focus tomorrow on two more rows and get everything back to level. I think my layout is good and the wrap looks good.
Thanks in advance for any advice.