I'd most likely buy as many wearables from my WL as possible.

Collections first. Then battle related items, and if I had anything left over, all the books I could get my hands on. :D

Pet slots! (Not that my current ones are filled yet, but you can never prepare for too many pets, right?)

Then potions and other items (TC and minions) for pets.

Leftovers would probably go to resellable wearables.

If I hadn't reached the maximum already again I'd spend my money on pet Slots for sure. Since that's not possible on pet related stuff (trasure chest items) and on my collections (stickers mostly).

This is easy....Wearables,Books,Weapons,and other odds n ends off my wl

wearables. alllll the wearables I could get. gotta get that 15k achievement, yo.

There's still 180m worth of pet slots I need in the MC

And I'm on a pet kick right now so I'd probably stock up on TC slots, at least for the pets where I know I'll need them. Probably knock out some WL items that I'm in general too cheap to buy myself, and now that I think about it/read the OP fully, some collection stuff too.

So tl;dr these:

1. Official Collectibles, meaning plushies, beanbags, stickers, tiles...
2. Pet stuff, including slots, potions and minions
3. Wearables that can be resold

Tons of stat boosters, maybe clear off half my wishlist and what not. Finish off a few pet treasures and the like.

I would get a combination of 2(food and books), 3(some for wearable purposes), 4(I would buy potions to get specific colors or experiments), 5(get most/all off my wishlist), and maybe 6(maybe get redeemable wigs if any sP left over). OR get an Ether + 2,4, and 5.

In the order of 4, 2, 3, basically all pet related. I'd only go to 2 if I've bought everything in . Same thing goes for 2 & 3.

4 pets slots there are never enough

-pet slots. lord knows i've got more pets than i know what to do with but lol when has that ever stopped me -boosters. esp intel and hp boosters

i'd spend 500 mil alone on that

food, toys for my pet, new items for my avatar.... I would probably buy 1 of everything lol and if I still had sp left, I would start all over until I ran out.

Probably stat boosters. Specifically INT and then in preferable order of HP>Strength>Speed>Defense.

Collections and books

alright, expect analysis of the information later this week.

Buy every SubQ item possible and then move on to stickers, plushies, and beanbags.

1. Official Collectibles: These don't do much for me unless I happen to really like one here and there. I don't have the patience or funds for the official collections.
2. Pet-related Collectibles: I'd spend a fair chunk of sP on food and books that I don't have for my main pet.
3. Battle related stuff: I'm just a Tier 5 battler but I'd like to get some decent things for my set.
4. Pet stuff: Yes. All the yes.
5. Wearables: Yes, but not for the intent of reselling.
6. Wearables that cannot be resold: I'd grab the ones I like.
7. Other I doubt I'd have any sP left after what I already listed but a custom user profile and a template for my pets would be cool. Art is one of the best purchases here imo but the Pet Spotlight isn't on my radar at all, it would just be for me.

Are you still looking for answers FOR SCIENCE?

3, 4, 5, 6

Also I'm not sure if pet treasure and treasure slots fall under "pet stuff" but I'd definitely buy some of that too. Basically, after pet slots, I'd work on paring down my WL. I'm sure I could easily spend 500m that way.

If I had anything left over, I'd buy art if I could.

I'd finally clear my Wishlist out which means it be spend on 5/6) clothes, 2) books and 3) weapons :P