Without the problem of Mahoro's lifespan her motivation for leaving Vesper's active service, her worry about Suguru's feelings at her rapidly approaching end, and the way she choose to fight Ryuga all loose their power.
The first season of Mahoromatic was very much (not entirely, but as a major element) about Mahoro planning for her passing. Kaerimichi, the title of the theme for year one was "On The Way Home" or "Going Home" (depending on who was doing the translating) that's always been a euphemism for dying. The second season, "Something More Beautiful" was about fighting back to avoid her end with the courage and love that Mahoro was learning from living with humans and most of all from Suguru.
Another thing to think about was covered in the mostly in the conversation between Leesha and Ryuga in the final episode, though it was touched upon at other times. Having a short lifespan effects the way you live. Mahoro, without the pressure of time working against her would be just another robot maid I'm afraid.
All that said, It would be hard to ruin Mahoromatic. There might be some good there. I really am worried about someone revising the story and only using the parts flavored to their personal taste. (All frosting and no cake?) I'm not saying that the last episode can't be bettered, but I think that it can be done while being consistent with the story in the first 23 episodes. I really think the 24th episode was a rush job to bring a quick end to the series and there would have been another six to ten episodes in a story which dealt with Suguru's struggles and Mahoro inside Saint trying to get back with him and maybe managing to help him in important ways from time to time. I think someone in producer's office said "This is where it ends, DO IT!" So they did.
Maybe EP24 was the way it was because the writers wanted to drive folks like us mad, in hopes we would keep it alive. I don't think a "sugar coated Mahoro" is a right or good thing. Broken hearts make memories that are very powerful. I would fix the broken heart, rather pretend it never happened.