If you are after "floorstanders" you will have a difficult time finding anything better than the Legacy Audio Aeris, or the Focus SE / XD. Either would do well in the large room you have (by volume).
But... if you want something that sounds very much like your ESL57’s, the Harbeths (30.1, 30.2, 40.1, 40.2) have a very similar sound with a bit more dynamics and bass - but, with that very life-like, rich sound, when driven by well matched electronics.
If you want, accuracy, dynamics, transparency, and detail resolution - you will find it very difficult to better the ATC SCM100’s and above.
But... if you want something that sounds very much like your ESL57’s, the Harbeths (30.1, 30.2, 40.1, 40.2) have a very similar sound with a bit more dynamics and bass - but, with that very life-like, rich sound, when driven by well matched electronics.
If you want, accuracy, dynamics, transparency, and detail resolution - you will find it very difficult to better the ATC SCM100’s and above.