I coded this to have lighter coord values in SVG path where the viewBox was excessively high. Resulting code is 20% lighter.

svg-reduce-viewbox.js

const svgTag = document.querySelector("svg");
const viewBox = svgTag.getAttribute('viewBox');
const elements = svgTag.querySelectorAll("path");

const ratio = 1/10; // changes this until broken paths appear

const charIsNumeric = function( char ) {
  return (char >= '0' && char <= '9');
}

const multiplyValues = function( content ) {
  let out = '';
  let chars = (content+' ').split('');
  let buffer = '';
  let buffercomplete = false;
  
  chars.forEach(function(char) {
    const isNumeric = charIsNumeric( char );
    if ( isNumeric ) {
      buffer+=''+char;
    } else {
      if( buffer != '') {
        out += '' +  parseInt((0- -buffer)*ratio);
        buffer = '';
        out += char;
      } else {
        out += char;
      }
    }

  });
  
  if( out[out.length-1] == ' ' ) { 
    var temp = out.split(''); 
    temp.pop(); 
    out = temp.join('') 
  }
  
  return out;
}

svgTag.setAttribute('viewBox', multiplyValues( viewBox ) );

elements.forEach( function(element) {
  let dcode = element.getAttribute('d');
  rcode = multiplyValues( dcode );
  element.setAttribute('d', rcode);
  if( element.getAttribute('stroke-width') ) {
    element.setAttribute('stroke-width', element.getAttribute('stroke-width')*ratio);
  }
  console.log({'in':dcode,'out':rcode})
});