Phone should at least be required to contain numerals, (I prefer. over - for separators in phone #s, but not essential)
postal code should be required to contain at least some numerals
I'd say address should also be required to contain some numerals, but I'm aware that there are a few addresses that don't actually have a number in them.
Validation of numbers or letters is not implemented. Recent validation improvements include:
- maximum characters for a text field
- date formats for custom date fields
- dropdowns have an automatically added "Select One" option which shows the field as not populated if Select One remains... allowing the field to effectively be made a required field.