This script can merge two multi-dimensional objects in javascript by comparing given object with the "re-usable" reference one and will remove additional keys nor adding missed parameters along with validation on values. Also it will return the default values in case of no input. IE8 and greater compatible.

script.js

/**
This script can merge two multi-dimensional objects in javascript by comparing given object with the "re-usable" reference one and will remove additional keys nor adding missed parameters along with validation on values. Also it will return the default values in case of no input.
IE8 and greater compatible.
**/
var module = (function(){
    //To make our reference variable onchangable, have to put it into a function which is fster and more efficient than "JSON.parse(JSON.stringify(VARIABLE))"
	var _defs = function(){
            return {
                   //string, number and boolean are actually regex based validation keys on input values.
                a: ["string", 'Defaul value for "a"'],
                b: ["number", 300],
                c: ["boolean", true],
                d: {
                  da: ["boolean", true],
                  db: ["string", 'Defaul value for "db"'],
                  dc: {
                    dca: ["number", 200],
                    dcb: ["string", 'Default value for "dcb"'],
                    dcc: ["number", 500],
                    dcd: ["boolean", true]
                  },
                  dce: ["string", 'Default value for "dce"'],
                },
                e: ["number", 200],
                f: ["boolean", 0],
                g: ["", 'This is an internal extra parameter']
            }
		}
		
		var _validation = {
				number: function (defaultValue, userValue) {
				  if(/^[0-9]+$/.test(userValue)) //Only numbers allowed
					return userValue;
				  else return defaultValue;
				},
				string: function (defaultValue, userValue) {
				  if(/^[a-zA-Z\s]*$/.test(userValue)) //Only A to Z case insentitive with space aloowed.
					return userValue;
				  else return defaultValue;
				},
				boolean: function (defaultValue, userValue) {
				  if(typeof userValue === 'boolean') //True or False or 0 ,1
					return userValue;
				  else return defaultValue;
				}
		}
		
		var _uniqueMerge = function(opts, _ref){
				for(var key in _ref)
					if (_ref && _ref[key] && _ref[key].constructor && _ref[key].constructor === Object)
					  _ref[key] = _uniqueMerge((opts ? opts[key] : null ), _ref[key] );
					else if(opts && opts.hasOwnProperty(key))
					  _ref[key] = _validation[_ref[key][0]](_ref[key][1], opts[key]); //or without validation on user enties => ref[key] = obj[key]
					else _ref[key] = _ref[key][1];
				return _ref;
		}
		var _get = function(inputs){
			return _uniqueMerge(inputs, _defs());
		}
		return {
		    options: function(){
			return _get(arguments[0] || null); // for more safety and control on number of input variables! used --> ( arguments[0] || null )
		    }
		}
})();
	
	
//How to use it:	
	
input_one = { 
    a : "Hello World", 
  //b : ["number", 400], //User missed this parameter
    c: "Hi",
    d : {
        da : false,
        db : "Hellow! World", // ! is not allowed
        dc : {
            dca : 10,
            dcb : "My String",
            dcc: "3thString",
            dcd : false
      },
      dce: "ANOTHER STRING",
    },
    e: 40,
    f: true,
	z: 'x'
};
console.log( JSON.stringify( module.options(input_one), null ,2 ) );
//Output:
/*
{
  "a": "Hello World",
  "b": 300,
  "c": true,
  "d": {
    "da": false,
    "db": "Defaul value for \"db\"",
    "dc": {
      "dca": 10,
      "dcb": "My String",
      "dcc": 500,
      "dcd": false
    },
    "dce": "ANOTHER STRING"
  },
  "e": 40,
  "f": true,
  "g": "This is an internal extra parameter"
}
*/
input_two = { 
    a : 32,
  //b : ["number", 400], //User missed this parameter
    c: "Hi",
    d : {
        da : false,
        db : "HelloWorld",
        dc : {
            dca : 10,
            dcb : "My String",
            dcd : false
      },
      dce: 73,
    }
};
console.log( JSON.stringify( module.options(input_two), null ,2 ) );
//output
/*
{
  "a": "Defaul value for \"a\"",
  "b": 300,
  "c": true,
  "d": {
    "da": false,
    "db": "HelloWorld",
    "dc": {
      "dca": 10,
      "dcb": "My String",
      "dcc": 500,
      "dcd": false
    },
    "dce": "Default value for \"dce\""
  },
  "e": 200,
  "f": 0,
  "g": "This is an internal extra parameter"
}
*/
//Empty input will return the default values!
console.log( JSON.stringify( module.options(), null ,2 ) );		
//Output
/*	
{
  "a": "Defaul value for \"a\"",
  "b": 300,
  "c": true,
  "d": {
    "da": true,
    "db": "Defaul value for \"db\"",
    "dc": {
      "dca": 200,
      "dcb": "Default value for \"dcb\"",
      "dcc": 500,
      "dcd": true
    },
    "dce": "Default value for \"dce\""
  },
  "e": 200,
  "f": 0,
  "g": "This is an internal extra parameter"
}
*/