Then maybe HD isn't all it's cracked up to be. If it can't even handle/adapt to showing older shows the way they were originally made I call that a flawed technology that shouldn't have been released until it could cope with it. The problem isn't with the original shows, it is with the new tech.
Clearly you don't understand the technology. HD screens can only display a true HD output if they have a HD input, but the DS9 DVDs do not contain a HD input, DVDs only contain SD images. All HDTVs and some DVD players have the ability to upscale SD images to HD but it is never as good as a true HD input because it doesn't have the finer details. This is not a problem with HD technology (HD has been in use on PC monitors for decades) the problem is that DS9 was produced for SDTVs because nobody realised that HDTVs were going to take off in the future. It was incredibly short-sighted on the part of the show.
As for redoing some of the effects shots, I have absolutely no problem with that. I remember rewatching The Maquis
when I bought the DVDs and the dissonance between the tense live-action shots and the simplistic special effects was very noticeable, the effects just didn't live up to the importance of that moment. And one thing which always annoys me is the explosions during the model shots; they couldn't afford to blow up the models because of how expensive they were so when a ship blew up they took the model out of the shot and replaced it was a random explosion. The Way of the Warrior
was incredible when it first aired and I loved every second of it, but those explosions niggle at me every time that I watch it. Sometimes parts of the ships disappear between frames, if they fixed those explosions I would be very happy.
The later battles when they switched to CGI were good because they could mangle the CGI models, there's some great destruction shots in Sacrifice of Angels
and Tears of the Prophets
. But those shots would also have to be redone because they probably were not rendered in HD. Not that DS9 will ever be remastered for HD, the show just isn't popular enough.