BuddyPress.org

What I did is I changed the form + validation stuff inside the template files to customize my own forms and validation process.

First of all I didn’t like the default validation process that BuddyPress is using where you have to push Submit and then the script checkes if every field is filled correctly, if not it pushes a text_message into the page through an Action.
Result, often the error message shows up at the top of the page where you aren’t looking and not at the form where the problem occurs, and even more important it’s an extra page-load to get this message into the page.

I didn’t like that so I left everything of that untouched as a back-up system and simply used my own ( Zurb’s ) validation JavaScript to check while writing if the fields are correct.
Plus this JavaScript disables the Submit buttons if a form or field is not valid.

This is a screenshot of the Profile Settings page but all forms work the same so you can just diff into the template files and add alter them.

The script I use is part of Zurb’s Foundation Framework so if you don’t like to work with Frameworks like me you have to strip all the needed code out of it.
http://foundation.zurb.com/docs/components/abide.html

There are probably also scripts like this one to be found online.