#1
"learning the London system and doing some study on a Sicilian variation"
++ That is wasted time and effort.
"I've managed to sneak up to 1500 blitz." ++ Get to 2000 rapid first.
"What am I doing wrong?" ++ Blitz and openings instead of rapid & endgames
"How can I get from 1500 to 1800?"
++ Play 15|10 rapid and analyse your lost games to learn from your mistakes.
Yo 1500 at 6 years.. see 6 years... I really can't believe it... Just... You know like... Play..... MORE
LEARN MORE,PRACTICE MORE WORK HARDER ANaLYZE YOUR LOST POSITIONS.. PRACTICE MIDDLEGAMES ENDGAMES.. KNOW MORE OPENINGS