Alright, I should probably lay my own cards on the table about this topic before I forget in a few hours. A fair warning though: I don't think I've ever posted a single review in the time since I joined the MB. Yes, I talk about addons I like on the Discord, but I've never posted a full scale review. (That's probably because one of my hobbies consists of playing tons and tons of custom maps and searching them top to bottom for emblems, so after a while some of them can start to blend in.)
First off, the requirement of 100 characters at minimum. I think this is a good change. A lot of reviews I see are things along the line of "this is good stuff" or "this sucks" without any further elaboration, so the requirement is a good addition, because it will actively incentivize going into detail about what someone liked or didn't like about a particular addon. Also, it means we'll start seeing less of this. (Not to be a jerk or anything, but I'm not exactly sure what to gather from this.)
Second, the removal of the star system as a whole. This one I'm very iffy on. On one hand, I can see why the decision was made and I can see the positives for it. Review-bombing can be a pretty big issue, and one that many things, not just SRB2 addons, have suffered from. Aside from a theoretical strongest review bomb, this is probably the one I think of most often.
Also, I agree with the notion that stars are not the only metric of what judges can addon's quality. I think all addons should, at the very least, be given the benefit of the doubt and tried out, provided they pass the requirements of what it takes to have your addon be hosted here.
On the other hand, it's now not as easy to check if an addon is a good time or not. Taking Adventure Sonic as an example, this addon having a 5 star rating instantly tells you that this is easily one of the jewels in the crown of "hell yeah, this is fantastic." With the removal of the star system, new users can't exactly tell which ones are pretty good unless they glance at the "Top resources" section on the left, thinking about it as I'm typing this, isn't hard to miss. There is also the "Latest reviews" section, which also might not be hard to spot, but I'm not sure if most people feel inclined to click on those.
Additionally, and this one might be more of a nitpick if anything, but now the space where the stars were just feels... empty. I wish I could elaborate further on this one, but there's not much to say. Maybe put some extra information like views, file size, or, hell, even the MD5 hash there?
Overall, I think the rating changes are so-so. 100 characters minimum for reviews is cool, but the axing of the star system is pretty eh, at least in my book. In all fairness, the two complaints I've given might fall more into nitpicks or "I'm looking too deep into this," but I just figured I'd lay my thoughts here before I forget later.
Alright, I'm going to back to RetroAchievements for the time being. By the way, you guys can keep the cards. Just make sure to spread them out evenly, I'd like to see how you deal your hands. Peace out.
