I Like it as is. The only real hang up I have over it is the voice work. The actors were tracked down and did their line readings into a tape recorder and put together later. Now, I know it's petty standard to no have everyone in the booth, but a lot of the readings were pretty flat and their tones didn't always match. Oh and some of the actors they reused to cover multiple characters in order to save money. This is fine if they're talented like Jimmy Doohan. But Takei, Nichelle and Majel just couldn't handle the changes and you can spot them a mile away.
Aside from that, Christopher is right: the animation is above standard for 1974 Saturday morning TV fare (don't look at it with today's eyes). The stories were really good considering the time slot and the audience. It DID win a daytime Emmy after all. Credit to DC Fontana, since she was story editor. And the music was great, something I'd love on CD - impossible as it is really.
So no, please don't touch it.