Not sure why you are limiting yourself to a sealed box design, but your comment about thin bass could be the reason. There are ported designs that can be placed along front and side walls and the ported design will give a fuller sound. The Focal range of speakers including Maestro, Scala, etc have down firing ports as opposed to rear firing may be an option.
Most underestimate the huge role electronics play in extracting what your speakers are capable of. Don’t confuse high wattage power amps with high current amps. The high current grips the speaker driver and gives you the low level detail you are searching for. Sub(s) may round out the lower registers, if needed.
I have heard Magico’s at shows and because of their sealed design, require gobs of power to extract the best from them. IMHO.
And I fully agree with the comments about Magico made by ghdprentice above.
Keep in mind the room and treatments play a large part. And finally, buying used affords you the ability to try speakers and/or electronics that would normally be considerably more if purchased new. Getting in and out of used gear has little downside and exposes you to lots of different options. Just my .02 cents. Happy listening.