Notwithstanding it's looks and plastic build, the M-CR610 never offered any changes or updates that were useful to me. If I wanted Spotify Premium i'd use it via AirPlay from my iPad and I have no interest in streaming 24/192 content.
Going by anecdotal evidence on this forum (and others) selecting inputs and changing radio channels would seem to be much slower on the M-CR610 and startup from standby with network connected much slower too. (I've lost count of people reporting intermittent network connection* on the 610 whereas my 603 has always been very robust.)
I still think Marantz 'missed the boat' by not offering an 'SE' version of the 603/610 (PM-CR810 maybe?) as a natural upgrade path and an alternative to going back to separates (or buying into something like the Naim Uniti range) to achieve the next step in performance.
*Although this may be due to people overreaching the speed and reliability of their internet connections and blaming it on the hi-fi.