Agree with others above in that this could be a tough ask, especially since you’re so attuned to what the the Opus’ do well. That said, there’s no reason you can’t have some fun going out to listen to other speakers (health issues aside of course -- hope you’re doing ok BTW!). Haven’t heard Avalons in a while, but I remember them to be quite neutral and they image like demons with a great disappearing act. It would be helpful to know what, if anything, you’d be looking to improve upon or is this just more of a 14-year itch you’re kinda feeling the urge to scratch. I get that.
If you can find Joseph Audio Pearls they might be worth a listen as they do many things similar to Avalon but their unique crossover may or may not captivate you. Could be more of a sideways move, but worth a shot. For something different that may or may not impress are the Carver Amazing Line Source. The grand scale and effortless dynamics line source speakers are capable of may be different and impressive enough to maybe sway you if you have the ceiling height to accommodate them. Last thought, Nola might be worth a listen if you can find them as their dipole design might be different enough to be interesting to you. What was I thinking not mentioning Vandersteen 5A? The additional bass of these speakers may be one reason to step up from the Opus. I’d mention Boenicke, but good luck finding them. Just some food for thought.
If you can find Joseph Audio Pearls they might be worth a listen as they do many things similar to Avalon but their unique crossover may or may not captivate you. Could be more of a sideways move, but worth a shot. For something different that may or may not impress are the Carver Amazing Line Source. The grand scale and effortless dynamics line source speakers are capable of may be different and impressive enough to maybe sway you if you have the ceiling height to accommodate them. Last thought, Nola might be worth a listen if you can find them as their dipole design might be different enough to be interesting to you. What was I thinking not mentioning Vandersteen 5A? The additional bass of these speakers may be one reason to step up from the Opus. I’d mention Boenicke, but good luck finding them. Just some food for thought.