Are the woodpecker super fence or incra wonder fence compatible with the grizzy table?
Are those more complicated fences really going to help with things like jointing 2" thick stock for guitar bodies or doing box joints?
I would have no problem throwing down the $750 for the loaded incra setup if its going to be something usefull and helps me but i'd rather not waste the money if its just a bunch of fancy gadgets ill never use anyway, since im not loaded and just starting out there are lots of other places the money could be used.
Not familiar with the woodpecker fence, but I can chime in on the Incra LS positioner fence. The LS positioner uses a fairly long arm. To take full advantage of the fence you need a much bigger table then normal, so I'm going to say no to being compatible with the grizzly table, or just about any other standard size router table.
The Incra wonder fence is designed for jointing stock on a router table. The only problem I'd see is finding a two inch long router bit.
The Incra jig comes with templates for making dozens of different box joints and variations.
My recommendation is you use your Grizzly table and use your old router. While you get comfortable with it you can take the time to build yourself a new router table for your new router and plate. Consider making it large enough for the Incra fence if you still decide to get one. If you have the room two router tables can be useful, or you can sell the old one.
In woodworking there is always more then one way to accomplish something.