Fixing my flat pronunciation (pitch accent experiment)

I used to sound so flat when speaking, especially with double consonants. So I ran an experiment this week recording my voice against native audio clips and analyzing the wave forms. Big difference. I realized I was cutting short vowels too fast and totally missing the slight pause in double letters. My rhythm score on my app went from 60% to over 85% just by exaggerating the pauses. Anyone else tried shadowing with