I don't use a "tree" as such at all.
I have devised a structure for giving every ancestor a unique identified code, based upon the generation and their position in it in the list of ancestors of that generation, listed in a strictly methodical order.
My parents are Generation A, with A1 being the code for my father and A2 for my mother; then my grandparents are Generation B with B1 being my father's father, B2 my father's mother, B3 my mother's father, and B4 my mother's mother; Generation C is my great grandparents with C1 being my father's father. father, C2 my father's father's mother, C3 my father's mother's father ... and so forth. This can be extended backwards indefinitely.
Children are then identified by reference to the code for their father (or, if he is not my ancestor, their mother). So my father's father's father had eleven children, who are designated C1A to C1L (I omit the letter I) respectively. One of those designations (and it happened to be C1B) is my grandfather, who is also B1. I use B1 to designate him ... but he also occupies space C1B so I do not give that designation to one of his siblings. I the distinguish between my grandfather's older and younger siblings by using capital letters for the final letter of his older siblings (only C1A, in this instance) and lower case letters for his younger siblings (C1c - C1l).
I then write a narrative account of the life of each of my ancestors, footnoting all references etc.; and I keep a separate document just summarising all of the ancestors I have identified (in the strict order of their unique identifier codes, but obviously omitting the codes for those I have not yet identified) with just names, maiden names and aliases, and dates of birth and death.
It works for me ...
