Where to improve phono chain?

My current system consists of Nola Baby Grands, A. Research Ref. 150 amp and A. Research Ref. 5 preamp, Tom Evans Micro Groove phono preamp, SME V arm, SOTA Cosmos table and recently re-tipped Jeff Rowland cartridge.

My musical preferences range from opera to jazz to rock.

I'd like to improve the phono section of this chain, but I'm not sure where to begin. My initial suspects are the Tom Evans phono-pre, or the Rowland stylus.

Any thought/opinions on this will be appreciated.

Thanks, Shaq