You could do a special version for Pandora owners with these filters
Dont bet on it. The pandora dont fall in the "with enough pixel shader capabilities"
Panmame has some really nice filters. How did mcobit do that?
Panmame use CPU filters. We are talking about GPU filters. a Pandora dont have the grunt to do a GPU filter as you want even the simpler one are too slow.
On the other hands, there exist CPU filters that are very fast and well optimised (thanks MH-T). That's what panmame use. Drastic already use all the CPU available for the emulation with nothing left for these filters...
Beside, if you have readed the other reply. Your TV is a large part of your problem here in this scaling issue : your TV scale up from NTSC format to HD. while the pandora only scale from DS resolution to NTSC. Your TV scale way more than the pandora does in your case. The issue for the jagged lines is the scaling...