1. Anchor system. I posted a description of a DIY anchor system based on a tie wire reel at
http://www.northwestkayakanglers.com/in ... #msg168110 . This system is particularly useful when fishing for big fish like sturgeon, where you want to be able to break away from the anchor system and leave the anchor line reel hanging from a buoy, so you can come back and re-attach to it after you're through being towed around by the fish. But I use it without the buoy to anchor my kayak when spearfishing.
2. Standing up. Fishing while standing up in an Outback is a bit of a stunt. Be prepared to end up in the water. If you want to do a lot of fishing while standing up, consider getting a Pro Angler.
3. Safety light. I posted a description of a DIY safety flag and light pole at
http://www.yakfisher.net/smffiles/index ... ic=10176.0 . Since you mention a nighttime 360 degree light, it sounds like you are familiar with the Coast Guard lighting regulations which are applicable to kayaks. To reduce the chances of confusion and accidents, be sure your lighting system complies with the regulations.
4. Gear tracks. I like gear tracks. They give you a lot of flexibility about how you set up your kayak, both from day to day, and from one part of a day to another. They allow you to change the way you have your kayak set up when fishing for new and different species of fish. They can accept equipment from a variety of manufacturers. And they allow you to improve the way your kayak is set up as you gain experience and see interesting ways that other anglers have their kayaks set up.
5. Fish finder and GPS. For some kinds of fishing, a fish finder with GPS is really valuable. If you're fishing in shallow water near shore or other landmarks, it may be no use at all.
6. Cooler. As soon as I catch a fish which I'm going to keep, I bleed it out and put it on ice in a cooler. I use a hard-side cooler, but a disadvantage of hard-side coolers is that they catch a lot of wind. I'd like to find a lower-profile well-insulated soft-side cooler which can handle bigger fish. I'm looking at the Reliable soft-side cooler, which Hobie is offering without the Reliable name on it. If you use a hard-side cooler, put a bungie over the lid so you won't loose your fish and ice if you roll your kayak, and strap it in place with nylon straps, not bungie cords, so it can't twist out of place in the rear cargo area if you get rolled in surf. A picture of my cooler setup is shown below. I replaced the cleats around my rear cargo area with Hobie padeyes, so I can attach equipment to my kayak more securely. If you get a cooler with wheels and remove the wheels, the step in the shell of the cooler where the wheels were can extend back over the rear hatch of your kayak, which will let you fit a bigger cooler in your rear cargo area.
7. Dolly. Check Craigslist for used dollies. You can save a lot of money.