After reading every translated Asa Project visual novel up to this point and revisiting a few routes that I hadn't finished yet, my conclusion is that Renai Royale is my overall second favorite Asa Project VN, behind Sankaku.
In terms of humor, I think Renai Royale is overall the funniest, consistently and constantly having the type of humor we've come to know Asa Project for: a mix of weird, wacky, over-the-top characters making stupid jokes and savage roasts at each other while still having occasional interesting enough melodrama at times.
Most Asa Project visual novels usually have some kind of unique gimmick like 0 Kilometer's family swap, Sankaku having everybody in a nerd club, Karigurashi having everyone be childhood friends, Koikari's rent-a-boyfriend premise, and the two-timing thing in Futamata.
However, in a weird way, Royale by not having a particularly standout premise—just basically all the main heroines constantly catfighting over the main protagonist even more so than usual (where it's typically maybe one or two heroines at each other's throats)—feels refreshing. Royale basically has all the heroines in love from the beginning and openly fighting with each other. Surprisingly, there aren't that many moege where the heroines are already in love with the main character from the start and handle it well, but I think Royale does a surprisingly good job with it.
Said catfighting along with the crazy humor definitely helps make the common routes stand out a lot. They give a surprisingly good amount of screen time to every character, even the side heroines. You can use the common route to figure out which heroine has the most appealing personality, backstory, or humor style because they all have their different styles of humor: Mari's overconfidence in being a childhood friend, Shione just being kind of a dumb rich girl, Nonoka being an insane snarky brocon, and Renna being a two-faced idol with insecurity issues. Yuna, a side heroine being the protagonist's ex-girlfriend for a while, is also something fairly unique for a moege.
However, the humor and the heroines' constant catfighting is the visual novel's greatest strength and its greatest weakness.
Despite the stupid, insane comments and constant roasting being really funny, if you're one of those people who expects this type of stuff to stop once you get on a heroine route… it does not.
In fact, you could argue the heroines get even more savage, many trying really hard to get with the main character despite already being in a relationship. I've come to not mind this since this type of comedy is mostly why I'm all in for Asa Project VNs, but if you're someone who prefers it when the route almost purely becomes about the heroine, then you're probably not going to like the routes much in Royale.
Asa Project titles already are a little bit on the short side compared to other moege, and while Royale does attempt to have some interesting melodrama around things like Mari being the MC's first crush, Shione and her relationship with her maid Ao, Renna being second fiddle as an idol to Yuna, etc., I find that they in a way feel more like distractions from the humor since the melodrama doesn't really go all in on actually developing the characters (with a few exceptions). Many times the mood gets “ruined” by going back to the comedy in some way or the heroines trying to jump in and take the protagonist away from the relationship as said above.
Like I said, I don't mind this type of writing that much, but it does kind of hurt the VN in a way where I can only really like it but not super love it because it basically only has comedy going for it, arguably in excess, to the point where the melodrama that's there I just can't take seriously. It's unfortunate since Asa Project does have melodrama that's actually done consistently well like in 0 Kilometer or Futamata, but I just don't think Royale quite got there.
But despite those complaints, I still really like Royale and not only think it's the funniest Asa Project VN, but one of the funniest visual novels I've ever read, which is saying a lot.
I would heavily recommend Royale for the comedy alone, but you have to like its style. It's definitely not your usual moege harem-style comedy, almost feeling like the Japanese version of South Park with how douchey everybody is to each other.
There is still enough heart and characterization to make the characters feel like actual people, but you just have to be ready for them to constantly be at each other's throats for comedy.
