Binary tree of most popular openings

I'm using chess.com explorer for this purpose starting with 4 plies (2^4=16 openings) and planning to go up to 10 plies (2^10=1024). Look here

https://www.chess.com/forum/view/chess-openings/pawn-structure-classification-codes

for the definition of pawn height (h), numerical code (NC) and PSCC codes of openings.

• 1. e4 c5 2. Nf3 d6 (Sicilian, h=5, NC=21, 2Ec1d )
  
• 1. e4 c5 2. Nf3 Nc6 (Old Sicilian, h=4, NC=2, 2Ec )
• 1. e4 c5 2. Nc3 Nc6 (Closed Sicilian, h=4, NC=2, 2Ec )
• 1. e4 c5 2. Nc3 e6 (Closed Sicilian, h=5, NC=21, 2Ec1e )
• 1. e4 e5 2. Nf3 Nc6 (Open Game, h=4, NC=2, 2Ee )
• 1. e4 e5 2. Nf3 Nf6 (Russian, h=4, NC=2, 2Ee )
• 1. e4 e5 2. Nc3 Nf6 (Vienna: Falkbeer, h=4, NC=2, 2Ee )
• 1. e4 e5 2. Nc3 Nc6 (Vienna: Max Lange, h=4, NC=2, 2Ee )
• 1. d4 Nf6 2. c4 e6 (East Indian, h=5, NC=21, 2CD1e )
• 1. d4 Nf6 2. c4 g6 (King's Indian, h=5, NC=21, 2CD1g )
• 1. d4 Nf6 2. Nf3 g6 (Indian, h=3, NC=21, 2D1g )
• 1. d4 Nf6 2. Nf3 d5 (Queen's Pawn: Symmetrical, h=4, NC=2, 2Dd )
  
• 1. d4 d5 2. c4 c6 (Slav, h=7, NC=21, 2CDd1c )
• 1. d4 d5 2. c4 e6 (Queen's Gambit Declined, h=7, NC=21, 2CDd1e )
• 1. d4 d5 2. Nf3 Nf6 (Queen's Pawn: Symmetrical, h=4, NC=2, 2Dd )
  
• 1. d4 d5 2. Nf3 c6 (Queen's Pawn: Zukertort, h=5, NC=2, 2Dd1c )

The tree of associated pawn structures:

•  h=2        h=3          h=4           h=5         h=6              h=7
  
•  Queen's Pawn:
•   2D                  -->  2CD   --> 2CD1e
•                                           --> 2CD1g
•                           --> 2Dd                     --> 2CDd   --> 2CDd1c
•                                                                               --> 2CDd1e
  
•                                           --> 2Dd1c
•         --> 2D1g
•  King's Pawn:
•  2E                    --> 2Ec     --> 2Ec1d
•                                           --> 2Ec1e
•                          --> 2Ee

We can distinguish 3 branches of height h=4:

• 2Ec Sicilian
• 2Ee Open Game
• 2Dd Closed Game