I've got over 3,000 points of painted Tyranids. They were my first army and I just wanted them at a decent tabletop standard, so I used every shortcut I could to get them there. Now I can't stand to look at any one model for too long as I've moved way beyond them in terms of painting skill. So now I've decided to repaint the entire army and bulk it up along the way!
This gallery should give you an idea of the old color scheme. The new one is almost exactly the same, but it's more what I envisioned when I made up the scheme. I changed it (Boltgun Metal claws, teeth and muscle, for example) to use some of my brother's paints and save my own money. I'm also changing the bases to a jungly scheme, like the Beastmen army I'm finishing up (link in signature).
The first model to get the new color scheme was a winged Warrior. The winged Warriors originally all used these wings (except with a rending claw at the hand), made from a rending claw, flesh hooks, and card. Now they have Gargoyle wings.
Not brilliant, but much better than before. And it should look great when applied to the entire army.
I just got two oldschool Warriors in the mail. I'm going to have one old-style in each brood to serve as the real brains. The idea is that each old Warrior uses Space Marine DNA (like the Tyrant Guard) and is capable of more advanced thinking than the other Warriors in the brood, which essentially act as bodyguards / fire support / synapse relays. But basically just an excuse to use these old models!