I just saw this so I'm sorry I couldn't help in time, but here are some tips to keep in mind:
One thing that most Americans (myself included) tend to do, especially on ich- and achlauts, is make the vowels fall back in their mouths. In actuality, German vowels are high in the mouth and a lot more forward than you'd think. Also, make sure you don't add any umlauts to words with pure "u"s (like "guten" is "goo" not "goe" ).
If possible, try to make sure your ichlauts are proper "ich"s and not "ick"s. "Ick"s are more Scandinavian than German.
Hope that helps for the future.