That budget would get you a set of Synergistic Research Element CTS speaker cables that will do exactly what you want - larger sound stage, more liquid and open- and with much greater dynamic punch. You could probably afford to have Michael Spallone upgrade their power supplies for truly jaw dropping performance. The main downside being when you hear just how much difference quality cables can make you will be spending a lot more money on them in the future.
https://systems.audiogon.com/systems/8367 (These have the Michael Spallone power supply mods)
Or you could add a full room treatment of Synergistic HFT, both room and speaker kits, not as staggeringly huge as the CTS cables but close.
But if it really is a deep wide dynamic liquid sound stage you are going for then ditch the ML and get a Raven integrated. You could probably sell the ML and AR for enough to get within $3k of a Raven Reflection MkII integrated, which will be an even more staggering improvement than any of the above ideas. Which is really saying something. https://www.ravenaudio.com/product/reflection-mk2/
https://systems.audiogon.com/systems/8367 (These have the Michael Spallone power supply mods)
Or you could add a full room treatment of Synergistic HFT, both room and speaker kits, not as staggeringly huge as the CTS cables but close.
But if it really is a deep wide dynamic liquid sound stage you are going for then ditch the ML and get a Raven integrated. You could probably sell the ML and AR for enough to get within $3k of a Raven Reflection MkII integrated, which will be an even more staggering improvement than any of the above ideas. Which is really saying something. https://www.ravenaudio.com/product/reflection-mk2/