The list seems a bit convoluted so far...
If you are intending to make a full English voicebank capable of covering Japanese phonemes, modifications to an existing list should give you good results. But if you want to make a bank primarily for Japanese but also have a bit of English support, I'd recommend just doing a CVVC and having extras like L and V and TH.
If you're interested in writing VV strings, I might be able to help somewhat? I am somewhat experienced in logicking strings.