Your email regex doesn't accept some basic patterns, like foo+bar@foobar.com. Also, a lot of newer TLDs can be longer than 6 symbols, like ".clothing".

See [1] or [2] for some inspiration.

[1] https://news.ycombinator.com/item?id=12448844 [2] https://news.ycombinator.com/item?id=9089129