Custom Language Support - error element ruins structure

Hi, I'm trying to implement support for a pretty easy language. My grammar is the following:

{
  parserClass="ge.freeuni.jack.language.parser.JackParser"

  extends="com.intellij.extapi.psi.ASTWrapperPsiElement"

  psiClassPrefix="Jack"
  psiImplClassSuffix="Impl"
  psiPackage="ge.freeuni.jack.language.psi"
  psiImplPackage="ge.freeuni.jack.language.psi.impl"

  elementTypeHolderClass="ge.freeuni.jack.language.psi.JackTypes"
  elementTypeClass="ge.freeuni.jack.language.psi.JackElementType"
  tokenTypeClass="ge.freeuni.jack.language.psi.JackTokenType"

  tokens=[
    SEMICOLON = ";"
  ]

}

File ::= Class 
Class ::= Property *

private Property ::= (static | field) (int | char | boolean) identifier SEMICOLON {
   pin=1
   recoverWhile=PropertyRecovery
}

private PropertyRecovery ::= !(static | field | int | char | boolean | identifier | SEMICOLON) 

My current problem is that I can't seem to tame error elements, they ruin program structure and I feel like it will be a problem in the future, when I try to implement more complex grammar with completion.

So maybe I am just doing something wrong an someone could put me in the right direction. All I want to achieve is this:

When I start typing a new property, I just want it to be a new PsiErrorElement under the JackClassImpl root and not destroy the structure of other properties. I.E: 

File: 
   |---Class:
   |---  |--- // I want to start typing here a new static property,
   |---  |--- // but while I am tryping s..t..a... the structure flattens (described below)
   |---  |--- Property:
   |---  |---  |--- field int bar;
   |---  |--- 
   |---  |--- Property:
   |---  |---  |--- static char foo;
    
File:
   |--- 
   |--- PsiErrorElement: sta....
   |--- 
   |--- PsiElement(JackTokenType.field)
   |--- PsiElement(JackTokenType.int)
   |--- PsiElement(JackTokenType.identifier)
   |--- PsiElement(JackTokenType.SEMICOLON)
   |--- 
   |--- PsiElement(JackTokenType.static)
   |--- PsiElement(JackTokenType.char)
   |--- PsiElement(JackTokenType.identifier)
   |--- PsiElement(JackTokenType.SEMICOLON)

I even thought adding a dummy identifier element so it doesn't ruin the structure but couldn't make it an error element, and I thought it was generally a bad idea.

So is there some easy solution, or maybe I have to create some utilities, neither that is a problem, I just really want to achieve this behavior.