Hand-rolling TSV is no better. The average TSV generator does not pay any mind to data cleaning, and quoting / escaping is non-standard, so what the other wide will do with it is basically playing russian roulette.

Using C0 codes is likely safer at least in the sense that you will probably think to check for those and there is no reason whatsoever for them to be found in user data.

Do you mean TLV (tag-length-value)? I can't figure out what TSV is.