Las Vegas vacation suggestions?

I've been to Vegas over 10 times, having been there often I have done the usual. I've seen the Bellagio fountains, Eiffel Tower, Stratosphere T.I. pirate show fremont street, i'm hoping to get some new ideals on things to try if there out there. If you have any ideals something different but fun let me know. I am going with my longtime girlfriend so couples activity's are also a good ideal. Basically what are you must see an do things in Vegas that the usual person might not now about.