Tree Syntax
Syntax: In linguistics, syntax is the set of rules, principles, and processes that govern the structure of sentences in a given language, usually including word order. There's a printable pdf version here. It takes qty 1- 8.5"x14" legal sheets in landscape.  It's actually readable 
Color Code   I don't want to make too much out of the color code. It's just an attempt to add a little color, and to change colors to help designate grafts coming into the tree from the outside.
 
 
 
 
 
  <The order is illustrated here
  The color names of the fill colors in Excel > Blue, Accent 1, Lighter 80%
  Green, Accent 6, Lighter 80%
  Also see screenshots below. Orange, Accent 2, Lighter 80%
Excel No doubt Excel wil evolve and change.  I'm assuming there 
will always be a spreadsheet application. 
I'm on a MacBook Pro in 2019.  The version of Excel that I'm using is pictured below.
Spouses
Spouses are shown above the tree member, in parentheses, in a new fill color, with a lower border line.
Second spouses are shown with double parentheses;  third spouse, triple parentheses …
If there were no children from the marriage, the spouse is shown in red.
If a spouse had children from an earlier marriage, and the children were brought into the household, the children are shown and are designated as (step).
If a spouse had children from an earlier marriage, and the children were not brought into the household, the children are not shown on the tree.
Adoptions
Adopted children are shoen on the tree like genetic children but are designated as (Adopt)
Dates
Life span is shown where known.  Years only.  Year of birth-Year of death 
If the person has died the years are enclosed in parentheses.
if the person is alive, the birth year is shown without parentheses, followed by a hyphen.
If the person has died, and if one of the years is known but not the other, the unknown is indicated by a question mark.  Example (1852-?)
if the year of birth is actually the year of baptism, then the year is preceded by bapt.   for example (bapt.1905-1972)
Fonts
People: Calibri (Body) size 12, not bold, not Italics left justified, bottom justified.
Arrows: Calibri (Body) size 18, Bold
Font color is black except where a link to other material is included.  That will be another color depending on browser.  It will also be underlined.
Row height 16
Column Width
Names 45
Arrows 4.5
Tree Arrows
:--> left justified, vertically middle justified. The colon designates either a first child or a last child.
| left justified, vertically bottom justified. This is just a limb going up.
:- left justified, vertically bottom justified. This is a stepchild brought into the household.
|--> left justified, vertically bottom justified. This is a middle child.  The arrow tip doesn't show.  Like hand-me-down clothes, the tip doesn't quite fit.
Names
FirstName MiddleName LastName=MaidenName
Nicknames are included rarely only if the we wouldn't recognize the person by their formal given name. 
Bogus data and placeholders
X's and ?'s are sometimes substituted for unknown
1900 is subtituted for unknown date of birth
If there is a known child but an unknown spouse, the spouse is designated with a placeholder.
The last name is shown and it is assumed to match the father.
There is one case of a person disowning us.  They are shown with an arrow, but their name is blanked out, and no further lineage.