If you do this, I guarantee you'll hear the word rice a lot.
There's nothing wrong with giving the interior some underglow, you just have to do it cleanly. Like the spoiler on the mustang. Some like it, some don't. But no one's calling it rice, like an aluminum wing on a civic. Is the OEM spoiler even functional? But because it looks clean and doesn't jump off of the car, it's acceptable. I would do a soft glow (even if you have to tint the bulbs), to the point where a person might not even notice it right away. If done well, I think it looks pretty damn good. Just my opinion...