We're actually missing the African forest elephant, which is regarding as a distinct third species. Obviously no one’s clamoring for it, so I’d call elephants satisfactorily complete regardless.
Disagree on apes. Great apes - sure, obviously. But I think gibbon variety will be nice.
Canines... we certainly have all the needs, but a lot of my selfish big wants are canines, and I think every one of the most likely next canines (a jackal, coyote, bush dog, tanuki, bat-eared fox?) are amazing so I'll keep coming back for more. But as far as needs go, yeah, I think we're good.
We might be at capacity for deer, but I'd argue that Pere David's is far too notable to close the door on.
For wild equines I could take them or leave them. I'm open to Grevy's zebra, wouldn't be opposed to the Somali wild fella, but I won't cry if they don't make it in. Same deal for giraffoids, I'd like to see the Masai giraffe but I'm fine without it. But we absolutely need a domestic equine in the donkey if support continues for long enough.
Hyenas and pangolins sure, I agree with you. Both of the remaining hyenas are a bit too out there, and pangolins are very niche as it is.
Penguins, no. I think we need, and will likely be getting, a third penguin.They're a varied enough species, often kept in mixed company, and are a bird that has actually managed to get into DLC twice now. I think a third one is reasonably likely.
Tapirs I'm on the fence about. Like, they're obviously a sort subject around here for good reason. But still, I like tapirs a lot, and I'm not going to pretend I don't want to see the Brazilian tapir just because the last tapir got botched.
Personally, I'd be fine without any more pinnipeds.