diff --git a/src/actions.js b/src/actions.js
index 0445970..d85090b 100644
--- a/src/actions.js
+++ b/src/actions.js
@@ -337,8 +337,7 @@ export function sort (eson, path, order = null) {
       orderedProps.reverse()
     }
 
-    const orderedObject = cloneWithSymbols(object)
-    orderedObject[META] = setIn(object[META], ['props'], orderedProps)
+    const orderedObject = setIn(object, [META, 'props'], orderedProps)
 
     // TODO: refactor into a set of move actions, so we keep eson state of the items
 
diff --git a/src/eson.js b/src/eson.js
index 259843c..4ec7ccd 100644
--- a/src/eson.js
+++ b/src/eson.js
@@ -101,25 +101,25 @@ export function transform (eson, callback, path = []) {
 
   if (updated[META].type === 'Object') {
     let changed = false
-    let updatedObj = {}
+    let updatedChilds = {}
     for (let key in updated) {
       if (updated.hasOwnProperty(key)) {
-        updatedObj[key] = transform(updated[key], callback, path.concat(key))
-        changed = changed || (updatedObj[key] !== updated[key])
+        updatedChilds[key] = transform(updated[key], callback, path.concat(key))
+        changed = changed || (updatedChilds[key] !== updated[key])
       }
     }
-    updatedObj[META] = updated[META]
-    return changed ? updatedObj : updated
+    updatedChilds[META] = updated[META]
+    return changed ? updatedChilds : updated
   }
   else if (updated[META].type === 'Array') {
     let changed = false
-    let updatedArr = []
+    let updatedChilds = []
     for (let i = 0; i < updated.length; i++) {
-      updatedArr[i] = transform(updated[i], callback, path.concat(String(i)))
-        changed = changed || (updatedArr[i] !== updated[i])
+      updatedChilds[i] = transform(updated[i], callback, path.concat(String(i)))
+        changed = changed || (updatedChilds[i] !== updated[i])
     }
-    updatedArr[META] = updated[META]
-    return changed ? updatedArr : updated
+    updatedChilds[META] = updated[META]
+    return changed ? updatedChilds : updated
   }
   else {  // eson[META].type === 'value'
     return updated
@@ -135,10 +135,7 @@ export function transform (eson, callback, path = []) {
 export function updatePaths(eson, path = []) {
   return transform(eson, function (value, path) {
     if (!isEqual(value[META].path, path)) {
-      // TODO: extend setIn to support symbols
-      let updatedValue = cloneWithSymbols(value)
-      updatedValue[META] = setIn(value[META], ['path'], path)
-      return updatedValue
+      return setIn(value, [META, 'path'], path)
     }
     else {
       return value
diff --git a/src/patchEson.js b/src/patchEson.js
index f004f35..ae8f02b 100644
--- a/src/patchEson.js
+++ b/src/patchEson.js
@@ -136,8 +136,7 @@ export function replace (data, path, value) {
   const oldValue = getIn(data, path)
 
   // keep the original id
-  let newValue = value
-  newValue = setIn(newValue, [META, 'id'], oldValue[META].id)
+  let newValue = setIn(value, [META, 'id'], oldValue[META].id)
 
   // FIXME: get the original expanded state of the copied value from JSON-Patch
   if (newValue[META].type === 'Object' || newValue[META].type === 'Array') {
@@ -190,8 +189,8 @@ export function remove (data, path) {
     const index = parent[META].props.indexOf(prop)
     const nextProp = parent[META].props[index + 1] || null
 
-    let updatedParent = deleteIn(parent, [prop])
-    updatedParent[META] = deleteIn(parent[META], ['props', index], parent[META].props)
+    let updatedParent = deleteIn(parent, [prop]) // delete property itself
+    updatedParent = deleteIn(updatedParent, [META, 'props', index]) // delete property from the props list
 
     return {
       data: setIn(data, parentPath, updatePaths(updatedParent, parentPath)),
@@ -235,14 +234,9 @@ export function add (data, path, value, options) {
       const existingIndex = props.indexOf(prop)
 
       if (existingIndex !== -1) {
-        // replace existing item
-        // update path
-        // FIXME: also update value's id
-        let newValue = updatePaths(cloneWithSymbols(value), path)
-        newValue[META] = setIn(newValue[META], ['id'], oldValue[META].id)
-        // console.log('copied id from existing value' + oldValue[META].id)
-
-        return setIn(parent, [prop], newValue)
+        // replace existing item, keep existing id
+        const newValue = setIn(value, [META, 'id'], oldValue[META].id)
+        return setIn(parent, [prop], updatePaths(newValue, path))
       }
       else {
         // insert new item