Well if you are not opposed to the idea of replacing the Strata, I would take that 10K and upgrade to a better amp/preamp combo. You already have a Terminator, so you don't even need the onboard DAC of the Strata. You might find this alone would give you quite an improvement even with your current speakers. And for sure it will be welcome at such a time as you do replace the Lintons.
Another option, since you have the digital side of things pretty well covered, is to upgrade the Rega and the PS Audio preamp. Honestly I could make a case for either.