IIRC I've paid 270 Autralian - not US - dollars for Ian's Über2next gimbals (plus 100 USD for Ernest's Hall sensors).
These gimbals do not only solve the (potential) center-play issue, they moreover remove the nasty (IMHO) "transition flats" (the stick gets "sucked" into the axes' travel when you move it, it's literally impossible to draw a circle) of the stock gimbals with their stiff springs - if you're flying WWII-sims, then the stock gimbals are too stiff for fine-control (but I've lived some years with them, though).
One question, if you don't mind: you're not planning to go 64-bit, are you? There are no 64-bit drivers available for the Cougar, nor are they planned before Vista will be available (next year). (They can be used under 64-bit, though, just not be programmed.) Just FYI...
As for which pedals to get, well, you don't really need game-port pedals and plug 'em into the Cougar - not for games that support multiple devices (most of today's sims). The only reason to plug pedals into the Cougar is if a specific game does not support multiple controllers, or if you need/want to program them via the Cougar's means. All of TM's old pedals fit, both the older and wider RCS as well as the newer Elites (both standard 1-axis pedals without toe-brakes). For CH's USB-port Pro Pedals you can find detailed instructions on how to add a switch with a game-port (so you can plug 'em anywhere you want) on Cougar World (but they come along with their own app so you can program them anyway). But the Simpeds are the best you can get if you're after fine-control (just like the TMs are the best when it comes to being (almost) indestructable), though they can be a bit hard to get: Peter Hofman was/is(?) very ill, and he's a one-man-show, plus he doesn't speak English; a friend of his is active at Cougar World, though, so you should be able to get them if you really should want them.