Generally, my opinion on the pack has changed very little.
I still think that if you want to have the complete zoo experience that you need all DLCs and with the Arid Animal Pack that opinion didn't change. So my ranking never really goes from "amazing" to "bad" but more of a "must have" to "buy when on sale" scale. For me this pack sits right between the "buy it next time you have some money to spare" and "buy when on sale". It's still a good pack to have from a zoo experience, but if you don't have all the packs yet I would suggest getting different ones first.
The overall feedback the pack got is in my opinion still justified, and I think my personal focus lies with the lack of diversity. Whilst I completely agree with the fact that these animals for the most part don't fill any new niches, I don't agree that that is a bad thing. Short term that is something that is indeed a bit of an issue; but long term I want to be able to switch up animals between zoos and not be stuck with just a bunch of animals I have to repeat over and over again.
Diversity wise, yeah, there I think Frontier did drop the ball a little bit. There are a bunch of arid and semi-arid areas all over the world and restricting yourself to only Africa, the area the game already has a lot of animals of, felt like a missed opportunity to me. There were animals that I would have wanted more, like a peccary for instance. At the end of the day I'm not said about the animals we've gotten, I think they're still good additions to a zoo game, but it makes me miss the other possible animals we could have gotten more.
On top of that though, I'm also still of the (albeit controversial) opinion that putting all your eggs in one basket (pun intended) and expecting that birds would bring something brand new to the game is well... going to backfire. Especially in the current model the community is expecting, being walkthrough and not walkthrough exhibits, I simply cannot see this big "new challenge" birds would bring to the game. I see no difference between decorating an exhibit with bats and decorating an exhibit with birds.
Even if the game would come with complete custom aviaries, as I would like them to be, I still think that that would still very much be a similar thing to what we have today. It's a new way of building habitats, but still building habitats nonetheless. People who grew tired of that will grow tired of building habitats for birds equally the same, and probably faster. Don't get me wrong, I love building habitats and building habitats for birds would be awesome; but I'm not expecting some kind of renaissance that only birds could offer.
To each their own though, it's not something I want to go into a huge debate about as I stand firmly with that opinion