The /ŋ/ sound is spelled with <ng>. The /ʧ/ sound is spelled with <ch> or <tch>.
This is a contrast between a voiced velar nasal continuant and a voiceless alveolar affricate, only occurring in syllable-final position or in syllable-closing clusters. It is not a problem.
The mean density value is low at 0.4%. The lists make 18 semantic distinctions, a loading of 78%.
clung clutch dung Dutch hang hatch hanging hatching hanged hatched hung hutch king kitsch pang patch ping pitch pinging pitching pinged pitched rang ratch Reading Redditch ring rich ringer richer sting stitch stinging stitching sung such swing switch swinging switching tongue touch wing which wing witch winging witching
John Higgins, Shaftesbury, December 2010.