When playing a track please provide the ability to click to do the following: 1) Select artist name of the track that is playing in order to bring bring up all their stored albums. Also option to go to album. 2) Select track name to see the album it belongs to so you can play additional songs from the same album.
While that’s a desirable list of player functions, that’s also some of the benefits you get from subscription players like Roon. It might be possible to side load something like the Fiio player (free, but a bit clunky IMHO) or maybe Poweramp player which is excellent and what I use on an Android phone with my Qudelix 5K plus IEMs for mobile listening.
I think those functions are somewhat basic. The stock Samsung player on android phones give you that ability. You also get the similar functions in bluesound node app.
Replay-gain is usually handled by the player itself, reading some metadata (more or less official and accepted...) tags. For example MPD (music player daemon, in Linux) IIRC does it this way.
Bluos, Squeezebox and I think Roon does it ths way too. ReplayGain would improve the usability of the internal music player significantly - for me anyway.