Unless you have some compelling reason to keep it, don't waste your money on the stock csi motor, really. The csi 3.0 is already 9.5:1 so its really not worth the money for custom pistons to bump up the compression. If you are inclined to stay with the 3.0 and the short block is still in good shape, then I'd spend the money on electronic ignition, a mild cam, head and intake porting and a header with free-flow exhaust. You should be able to get the D-Jet to run that with some tweaking since the new Schricks are pretty mild on the duration, but make up for it with increased lift. You may gain 20-30 hp. I don't know what the RWHP would be -- probably still less than 200 at the wheels.
On the other hand, if you really want a noticeable performance upgrade, I would suggest getting a 3.5 block and start there. I just built mine for well under $2k with a Schrick cam and 9.5:1 pistons (or thereabouts) farming out the machine work (block hone, valve job, rebuilt rods) and assemblying everything myself (including the valvetrain). This includes all new bearings, rockers, timing set, oil pump, etc. -- basically everything was renewed. It will blow the doors off the 3.0 that was in there. The only caveat is whether you can get it to run with the D-Jet. I didn't even try to run the D-Jet on mine and went straight for the programmable ECU. Unfortunately, that adds extra $$$ that would probably put you above the $2k budget. I think you can get the D-Jet to run this combo with some tweaking (increased fuel pressure, MPS adjustments, temp sensor resistors, etc.), but you'd need someone knowledgeable to get it set up right.