It will have a few revised stages and some entries you may recognize from the OLDC, but its not really got the center of attention because the development team considers Circuit mode the lowest priority for the time being. The biggest improvement is the fact that Circuit mode is no longer as laggy as it used to be... but it is most certainly not at the stage the other gametypes are at.
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As for the stages you listed, many of those played very poorly despite any popularity they might have had. It's also worth noting that the new system will make any of the older stage designs clearly outdated. Tree Ring, I believe, serves as a perfect example of an outstanding 1.09.4 stage that won't work in the new gametype simply because it wasn't made for the new system. For that reason, most of the returning maps have been revised, as you can see in the first post. Meanwhile, Jade Valley and Noxious Factory were able to make a comeback (to some extent) thanks to the new system which makes the size which ended up getting them canned beforehand actually work to their benefit.
There are also maps that try to live out a concept that has failed in the past. Hydro Plant obviously has its flaws as a water stage, so Mystic took what we have all come to know about it, and worked them into Tidal Palace. Noxious Factory was reworked to be less obnoxious with its factory gimmicks, and Infernal Cavern tries the hazard based gameplay again but this time with much more success.
You cannot imagine how much thought had gone into the design process of each individual level behind the scenes, even for those one might have expected to be a shoe-in. I believe Sapphire Falls and Silver Cascade are both good examples of very standard and memorable maps that were added very late in the development process because of the difficulty with converting them effectively.