Height 6ft 2
Skill level - intermediate
Here's the bad news: What you're looking for doesn't exist. There is no single ski that can help an intermediate ski deep powder competently and also perform optimally on piste, for one thing. And for another, a lot of this stuff is a matter of taste.
But we can't even help you find it, because you've told us next to nothing. Where do you live? Where do you ski? What type of terrain do you prefer? Are you trying to improve and branch out into new terrain, or are you a terminal intermediate?
Standard advice: Start with getting yourself a good pair of boots that fit you. They're the only things you really need to own rather than rent or demo, and without good boots that actually fit you, no skis will perform properly. Some people on this board have enough experience to be able to figure out what boots fit them on their own, but most -- including me, and I've got 300+ days over the past seven years -- need the services of a good bootfitter to find the closest thing to a perfect fit for your feet off the rack, and then tweak the boot to get it the rest of the way.
If you tell us where you live, chances are, we can refer you to a few good ones.
TheDad got it right about boots. They are THE most important piece of gear there is for skiing. And what he said about there not being a single ski that does groomers, powder and park even marginally well is also correct. Go to the "Ask the Boot Guys" forum and read the wikis about terminology and fitting, then check the list of fitters and contact the guy who lives in Great Britain(yes, there is one). Get properly fitted boots from him before you do anything else. Properly fitted boots will definitely help your skiing improve, but skis will not. Trust me, I know because I wasted a lot of money on hot skis before I found that the real answer was the boots. Demo a lot of skis this next season and see what you like and what seems to work well for you. Not all people like the same skis. Last season I was down to either a Line Prophet 90 or a Nordica Steadfast. Lots of people on here really like the Prophet 90 but when I skied them in our steep narrow chutes, they were incredibly "hooky" and just not comfortable. The Nordicas made me love the chutes because they reacted instantly and never hooked up on me. Demo skis based on recommendations but don't buy skis based on recommendations.