Let's see, for the Direct itself, I'm hoping for:
-Something pertaining to the datamined crops.
-Minor quality of life upgrades, especially a cart for the Able Sisters. Another storage upgrade would also be incredibly appreciated—I'd rather not make extra player characters solely for added storage space. I like collecting clothes though, so this is... desperately needed in my current situation.
-Fence customization!!
-Any news regarding the mysterious HHD update... DLC... whatever it winds up being, if anything, I just know that I want it ahahahah.
And things I'm hoping for in future updates, but that I don't necessarily expect to see in this Direct:
-Some sort of workaround for all the color-locked items (Nook Mile redemption ones included) that doesn't involve Nintendo Online or pure random chance. I'd love it if they brought back Reese and Cyrus outside of the wedding event for this, but I'll take anything really.
-The missing fruits, and preferably perfect fruits as well! They would add so much color and variety; I miss them. Similarly, I want violets, carnations, clovers, and dandelions back too. Dead trees would also be really awesome to see again—I love the spooky tree, but I like having dead trees around in late autumn through winter as well, to add to the wintry atmosphere, and it's too Halloween-y to work for that.
-Also, the missing furniture sets and items from New Leaf!! I miss the Rococo and Princess sets a ton, as well as a few of the miscellaneous flower set items and food items that didn't make a comeback. ;; Some of the PWPs from New Leaf (wisteria trellis! windmill!!) would be amazing to see converted into furniture items, too.
-Permanent shops for Leif, Kicks, and Label. I'd also love to see some more NPCs return, like Gracie, Booker/Copper, Katrina, Blanca, the list goes on.
-At least one more upgrade to Nook's Cranny, if not two. If that involves any of what I've listed above, even better.
-I didn't think this was terribly likely and I'm still not getting my hopes up too much, but since we might be getting some returning or even brand new villagers in the fifth Amiibo card series... more optional villager slots.

Ideally, I'd like 6 more, so 16 villagers total—that's enough for two of each personality type (and one of each sub-type, for those who take that into consideration). I'd
love if Series 5 gave us more new villagers (I especially want some lionesses, and missing species/personality combos), but it'd be a little painful to have to rethink my dreamies.
Even if we don't get any new or returning villagers, though, I'd still absolutely love to have six more villagers on my island. I can already think of a few villagers I'd love to have, if only I had more room for them.