Marantz PM 8003 v Rotel or NAD sperates

I much prefer integrateds but do not want to go backwards Understanding the power differences would there be any reason from a sound quality perspective to go from say a Rotel RC 995/RB 990 or NAD C162/ 272 to a marantz PM 8003 integrated? I had one while ago but now have different gear so not sure.
The first thing I would consider, is the companies you list, are all known for making integrateds. They do make separates, but I don't think they would a very big step up in terms of sound quality. I think the best thing you can do, is to go audition some new gear, but don't pre judge it based on the design. Just pick the one that sounds the best, regardless of design.
When I owned the NAD C162/272 combo, I felt it sounded much better than the top NAD integrated of the time the C372, and well worth the additional cost.
though if you prefer Integrateds there are many very good ones in that price range.
I already have the seperates and one pair will be leaving for sure. Just not sure which one The other option is to get rid of both pairs of sperates and get the 8003 AGAIN.
After reading your 2nd post, I realized that I didn't fully understand your first. Now that I do, I can't see how anyone could answer your question in any meaningful way. You have the NAD and Rotel separates and used to have the 8003. Its highly unlikely any of us has ever owned this combination of gear. If you're having a difficult time evaluating these components, how can any of us do better? At best, we would just be guessing.
I think you would sacrifice sound quality. I have an 8500 and a variety of separates from McIntosh, Acurus,SAE,ATI,others. I bought the 8500 to try a modern integrated. I like it but its different than the other gear. Less warm and more sterile. Better detail but it has less presence. I think the tradeoffs made in design and cost for an integrated disadvantage it atthe lower price point. I think you would need a higher value integrated to come out ahead.
Have you considered some of the Yamaha offerings?

Some with built in DACs like the A-S701, A-S801, and some straight analog like the A-S1000 and A-S2000. I have the A-S1000 which is a 48.5 lbs powerhouse driving a pair of Klipsch RB-75's and I could not be more pleased.

An NAD C375BEE or C375DAC may be options?