If you have good LCR speakers, switching to an integrated makes no sense. Not knowing the models of your Mirage speakers does not help in making a recommendation because they have many versions. They have HDT High Definition Theater LCR's $1500.00 each. They OMC-2 center speaker which also an LCR $350.00 each or they have OM-Sat series which are compact monitors. Using an integrated amp has too many limitations for Home theater. First is connectivity. Most integrated amps are analog, most tv only have optical or Hdmi ARC outs, most new cable boxes don't have analog outs anymore, 99.9% of blueray players don't have analog outs. So unless you have a Sony Tv, the only major brand with analog outs, both Lg and Samsung are digital only. So to use a digital only tv with an analog integrated amp would require an optical to analog convertor and the tv would have to be able to convert bitstream or dolby digital to PCM. If you purchase an integrated amp with digital in then you will be ok as long as the tv can convert bitstream/dolby digital to pcm something that most panasonic tv cannot do. So logical thing to do is to upgrade the receiver. This allows for any easy switch from multi channel to pure direct for 2 channel. If music is the focus, then a new Marantz or Denon with modern Dac's and phono input should be fine so both worlds are integrated with minimal degradation. If you get a receiver with pre outs, you can always ad an amp for a better 2 channel experience and still enjoy better clarity with movies in multichannel. You can always add a better phono preamp for vinyl. The last issue with an integrated amp for video is with a simple soundtrack the phantom center image is fine as long as you are dead center between the speakers. Clarity will suffer when there are multiple listeners off axis. Modern soundtracks suffer the most because of their dense mix and poor dialog mix resulting with movie soundtrack drowning out the dialog.
It all depends on what limitations you are will to live with. The other suggestion is having a dedicated system for music and 1 dedicated for movies. I am 30 year sales veteran in the A/V business and I have advised a few people on this matter. I sold and currently own Mirage HDT LCR's with Denon's previous flagship Avrx7200 which I use pure direct for music and dts virtual x for video. I have 2 dedicated 2 channel rigs for music and a 2 channel rig for video in a small room. With the latter, I do notice the lack of dialog clarity with complicated & dense movie soundtracks.
It all depends on what limitations you are will to live with. The other suggestion is having a dedicated system for music and 1 dedicated for movies. I am 30 year sales veteran in the A/V business and I have advised a few people on this matter. I sold and currently own Mirage HDT LCR's with Denon's previous flagship Avrx7200 which I use pure direct for music and dts virtual x for video. I have 2 dedicated 2 channel rigs for music and a 2 channel rig for video in a small room. With the latter, I do notice the lack of dialog clarity with complicated & dense movie soundtracks.