I'd say it's about time. TNG is/was my favorite of the Trek tv-series, until I became acquainted with the crew of DS9. Still, as TNG was the first show I ever watched, i'd love to see it remastered into the 21st century. Things i'd like to see remastered, are everything involving the Borg (adaptive shielding effects for ex, especially during Best of Both Worlds). Riker's reference in First Contact to being able to see several cities on the moon, with the naked eye. Would be nice if that were applied to any episode of TNG where the Enterprise is orbiting/visiting Earth.
Neither DS9, VOY or ENT needs remastering, but I could definitely see some remastering done to some of the effects-heavy episodes of DS9. Most notably, during the latter half of the Dominion War arc, in which (due to budget), the powers that be decided to reuse alot of the old battle scenes.