Tweaks for a new ARC preamp?

Out of touch audio fan updating (a bit) a vintage system. Preamp is an Audio Research LS2MKIIB with remote which has been mine since 6/1994. Currently on a Siemens and Halske 6922 Cca grey plate with grounded tube cooler and the unit on spikes.  Sony XA5400 ES CD/SACD run balanced through to 2 Sumo Andromeda 2A amps with one amp each running an Acoustat 1100 ...  one channel on panel, one channel on base module.  Secondary source is a Sansui TU-9900 that has the works done by Mike Williams at Radio X including Burr Brown op amps.  All cabling is Straightwire Maestro or Virtuoso and the CD to pre to amp legs are run full balanced.  Room is treated by Acoustic Sciences

Strongly considering a strong deal on a brand new Audio research LS17SE and would like to know from those who have some much more current experience than mine about tubes (other than stock), power cords, etc., as possibilities for the new pre, should I execute the purchase.

Present system has great dynamics and soundstage, imaging is excellent but timbre and musicality are areas I expect to improve upon the change.