I think you will notice the difference, and the Frerot is a good choice. I think you are on the right track in keeping your expectations in check. You are only just starting down the digital rabbit hole, be patient and let your impressions of the gear form over time.
Do you recall "instant improvement" from your first stand-alone DAC ?
After weeks of research I recently ordered my first external DAC. My system is modest by most accounts... Van Alstine SET400 amp, T-10 tube pre-amp, Salk HT2-TL speakers, WiiM Ultra streamer/DAC. It sounds very good to me... resolving, clear, excellent bass, mids, highs. Then I started reading and asking about streamers and DACs and it seems my system could sound better. So I did a lot of reading and ultimately ordered a used Merason Frerot with factory wal wort power supply. Now the anxiety of second-guessing my choice and what it will sound like in my system. Cuz there are no stores near me to demo DACS. Eventually I will likely upgrade the streamer.
What did you notice the most about your first stand-alone DAC... more clarity, richness, scary good vocals, extended highs, more airy highs, more and better bass ? Better soundstage and imaging ? All the above ?