I've had my card for a year and just now received my very first auto CLI. I've been hitting that Luv Button literally like every day and haven't gotten a CLI in over 6 months. Then I log into my account last week and see that my available credit is now $6,000 instead of $3,000! I use the crap out of this card, so I'm not sure why I couldn't get one earlier. You got an amazing SL; I'd certainly be happy with that SL!
Don't think the denial when you tried for Discover luv is a firm no. I tried, got the no, then a couple days later saw the increase. It was crazy but I'll take it.