Should I trade-up from my Krell KAV 300?


My system is a Krell KAV 300, Meridian G08, and Thiel 2.3 speakers. My interconnects are Creative Cable (Music Direct used to sell them for $375). My speaker cables are Synergistic Research (about) $500. My room is small and I listen at relatively low levels, mostly classical piano, some symphonies.
Should I invest in a used Krell KAV 400 or instead invest in better interconnects or speaker cables?
Thanks for your help.
runfast
Or better still - high sensivity speakers with a SET amp. Such a combo offers much different sonic perspective, but at a cost.
You should really put the whole product number because they use KAV300 (something) on several things (even know this is the AMP section)

Anyway, I have the KAV300CD player and I would not trade it for two reasons. 1. It is the best sounding player I have heard, AND i have owned and used many many high end players 2. Since it is basically a TEAC, it is 100% repairable, as mine has been, by any local repair guy worth his salt. Unlike some other models that are Philps, which from what I undersand, are not always repairable and when they die you are SOL.
FWIW, I just auditioned some integrated units and it came down to a bakeoff of the 400xi and S-300i. I went with the S-300i. Both were great amps but as already mentioned the 300 sounded warmer in all ranges and, with my system, was more flexible with various source recordings. The 400xi was not as kind to recordings that were less than excellent, at least with my system (IMF TLS80 speakers, Rotel 991 CD).