Strong denoising and flattening a cartoon source

[Homei]

I'm trying to filter Invader Zim which seems to be very poorly mastered to the DVDs and thus poses a very difficult source to filter. I tried filtering it for countless hours, but it never pleased me, so I seek your advice.

Here's a short sample that shows some artifacts that are the most difficult to get rid of for me: Mediafire (33MB zipped m2v and d2v)


The ground is the biggest problem here. It was impossible for me to get a nice and flat area. When filtering, it would smoothen the areas, but create edge noise.
I also see some haloing in the top left part of the image, but I can live with that. Additionally, one can observe aliasing. I was able to anti-aliase it.


The problem here is the heavy blocking that destroys details. Look to the right of the lightning. After filtering, that area was muddy.




This part seems to be suffering from MPEG2 bitrate starvation. Again, I was not able to clean the areas.

This is what I did:

MPEG2Source("G:\Zim\01 - The Nightmare Begins.d2v", cpu=0, info=3)   # I also played around with cpu=0, 2, 4, 6
ColorMatrix(hints=true, interlaced=true, threads=0)
tfm(d2v="G:\Zim\01 - The Nightmare Begins.d2v")
tdecimate(mode=1)                                                    # The last two lines are immaculate inverse telecining

UnDot()                                                              # Used sometimes and sometimes not
Toonlite()                                                           # To strengthen the lines for denoising afterwards

sourceclip=last

MCTD(\
sharp=false, \
protect=false, \
AA=true, useEEDI2=true, maxd=24, AAthr=32, method=2, \
deblock=false, \
edgeclean=false, \
stabilize=false, \
enhance=false, \
GPU=false, \
settings="high")                                                     # I tried out a lot of settings. Sharpening is off because it
                                                                     # would cause aliasing. EEDI2 is preferred over SangNom because
                                                                     # the latter would cause artifacts.

LSFmod(strength=75,source=sourceclip,Lmode=0,soft=0,ss_x=2.0,defaults="slow")

The result is O.K., but not quite what I want.

I mostly want to flatten the areas like in the first image. Filtering the blocky parts would be just a bonus because they appear sporadically.

I don't mind if it takes a 3fps script to filter this, but I would be very glad to hear your suggestions.