As Saphron's predecessor, I've also been faced with many of these challenges in Medivia development, so before you bash him, try to understand some things.
If some sprites look bad, the skill of the author may not be the sole reason. I'm not trying to make a cop-out here, these are facts and here are some of the factors that could be applied to this situation:
First of all, I can't imagine the amount of work he had to do to replace the sprites of the entire game within such a short timespan.
Such pressure can tackle entire teams of people at once, sometimes bringing whole projects to ruin, let alone a single member.
This is already a major handicap for anyone, not just artists. Working under pressure is exhausting and stressful, and simply can not result in greatness.
I think the decisions that lead to this situation could've been handled better by Medivia team, but then again, it is not mine to question the executive decisions over there.
Another big thing is the Medivia style. Medivia has demands for a very very unique style that probably nobody else in the community is gonna ask you to do. The sprites have to look old, serious, dark, to fit the Medivia fantasy. But if you're thinking 7.4 style, then you're wrong.
Medivia wants an unique style. They have to be 'a bit more modern looking' than 7.4 , but not too modern looking to the point where they would seem like they belong in a different game.
It's a very niche style which has to be defined and developed by Medivia's artist. There is no tool in the world which you can use to practice this other than raw experience with it, so give it time. But proper time, not this "rushing under the pressure of the world crumbling before you" time. Let Saphron get under its skin and the results will keep getting increasingly better.
I was fortunate enough that I began when no other custom environments for Medivia had been built, so I had the opportunity to lay down the foundation for it. However, even that foundation had to fit with the rest of the existing environment at the time, so I couldn't deviate too far with the style either. Saphron had to deal with not 1 layer of this issue, but two, since there were both original and my own sprites that needed replacing.
I was convinced when Saphron took over, that he would instantly do everything better than I did, because Saphron's spriting style inherently is much closer to what Medivia wants.
I had to deliberately make some of my sprites worse (in my opinion) in order to get them to look fit for Medivia. Imagine that concept of having to make your work worse in order to make it better. That's paradoxical.
Between the first publication of the update and today, Saphron has already shown he's willing to listen to the community ideas and proposals, but comments that contain only insults and no feedback that can be used to make improvements serve for nothing other than to demotivate the artist.
If Konrad wanted, he could've skipped both me and Saphron and just went for some other proven artist from another community that has nothing to do with OTs. However, he invested in people from within our community and built us from noobs into decent spriters. This makes both Medivia and this community as a whole better, because even if we're not working for Medivia, we'll be a part of this community and we'll have meaningful skill to contribute within it. There's something very positive about that. You're all here on this forum for OTs, so if this guy is single handedly creating one of the most custom OT based games ever, and also investing in the members of the community while at it, he should be thanked, not bashed on for his decisions.
The player expectations are also wild on Medivia. You don't know what to expect from these guys. Some of the shittest sprites I've made have been well received in Medivia community, and some of the sprites that I thought were good were absolutely hated. So go figure. Probably has to do with my previous point about that paradox.
There is a lot of points to be made here, but I think this post has already gone on long enough. Sorry to see that the initial experience for you was more-less negative like this, Saphron, but trust me that it only keeps getting better after the initial shit has passed and you get some time to improve in areas you figure out are lacking. Looking forward to see more