The PS4 is the only chance the Vita has at making a comeback in the west. Great games and a price drop weren't enough. Over in Japan things seem to be improving already and I'm not an expert on their opinions, so I'm going to ignore that region.
1: 1st Party Vita Grip for Home Remote Play
The Vita is no DS4. This is great for portability, but it's bad for home use. The grip needs to be similar to the circle pad pro and add in the missing DS4 abilities. R2 and L2 are a must, while rumble, a light bar, and L3 R3 would be optimal. As a result the Vita and its cradle become the perfect local companion device for the PS4. It can simply replace a DS4, be used for remote play, or even offer Wii U like features. I know the Wii U isn't doing too hot, but it would be smart to be prepared if Nintendo turns things around. Basically it would be like releasing Move in 2007 instead of waiting for the fad to fade. Plus Sony could highly encourage devs to have feature parity if the game has a wii u port.
2: VITA.TV in the west
Position the device as an Apple TV killer. PS4 remote play, GAIKAI, and entertainment apps are way more than enough to sell the $99 system. Only thing that needs to be worked on though is the controller. DS4 is perfect for most things and the DS3 is great for saving money, but the casual target market wants a casual device. Make it compatible with the PlayStation APP and boom.
Then there's that whole Vita thing. I doubt many of these casual buyers will be interested in buying physical vita games. However they could enjoy downloading some cheap games. Big budget exclusives are dead on the portable but $10 indies could be very successful. The more indies drawn in the better the portable hardware sales should be. Great sales? No way, but still better than nothing.
3: Price Drop again
The Vita is in an interesting position right now. It's not doing that badly for Sony, despite what people think. This is actually a problem though, because it stops Sony from doing everything they can to save it. When the PS3 was floundering, they lost billions and turned that ship around. With Vita it would be financial suicide to invest as much into it, but they still need to do something to help its fate. Drop the price to $150, but keep those memory card prices the same.
4: PS4 Bundle
This is kinda already happening with all the other bundles, but retailers are using the PS4's low supply to force consumers to buy more. Sony needs to release a $600 (yes you poor people don't save any money) PS4 and Vita bundle ASAP. Maybe through in both Killzones if they patch in cross-play support. It can't be priced lower than buying them separately though, because otherwise it just bleeds money for Sony and puts a lot of cheap Vitas on EBAY.
5: Unique Games
Cheap to produce games like Tearaway that are also critically acclaimed masterpieces are what the system needs. Although I personally loved Mercenary, I have a PS4 now and will just play Shadow Fall instead. Vita needs new ips and experiences that would not be better on the PS4.
6: GAIKAI
Although piracy killed the PSP's software sales, it certainly helped with hardware sales. GAIKAI is the best alternative for Vita since it allows gamers to have their huge collection of legacy games while not affecting Vita game sales.
