I'm dumb, or don't recognise the term data-capture... can you describe better what that is?
If this is an HTML form your points are good. You can have client-side validation for the purpose of helping users put the right info in the right field in the right format the first time, but all that data is tainted and your server MUST revalidate it. It's always considered tainted.
If normal people are filling these forms in (assuming these are forms, again not certain what data capture means exactly) you'll maybe want to do some search-engine searches for "HTML form usability" since how a form is built can really affect how much good data you get from people. That is, difficult forms will make people quit, and confusing forms may give you incorrect data.