LT's and PCM should add about 30rwhp and bring up your hp/tq curves at lower RPM's to much better levels.
Would bet that you wouldnt see much difference if you did the above and then added the Volant afterwards. I would spend that $ on a set of mids and catback. Mids, catback and a drop in filter should give you another 30rwhp.
Next, look at replacing your shifter, Master/Slave unit, Clutch and Flywheel ....As the added hp/ft lbs will make your shifts more difficult and start to wreak havoc on the stock clutch.
Traction is always good, so a set of Caltacs and DR's would be a good buy
Not much else to do expect perhaps a throttle body without improving internals or power adders.