I've added slots to each of the toilets that had enough space for objects to be placed on them.
In total I've edited 14 toilets (including base game and all packs). I've not added any swatches, they are all the original EA colours.

Some toilets aren't included because there wasn't enough space to put slots without it looking out of place, or that the objects were defying gravity.

I'm always using the 9 and 0 keys with moveobjects to maneuver things onto my toilets. So I thought I'd make it easier and add slots so it just snaps into place.

I haven't changed the location in the build/buy menu, or the price of any of the toilets. They are all found in plumbing > toilets

May conflict with other mods that edit the toilets listed below

This is an OVERRIDE it will REPLACE all the toilets I've added slots to

You can download the all in one file if you own all the packs.
You can "mix and match" the downloads by downloading the base game toilets + whatever packs you have installed separately (each are labelled for which pack you need)
The base game toilets are seperated if you don't own any packs at all



Edited toilets & number of slots:
Base Game
John (5 small), Modern Relief (3 small), Old Time Antique Toilet (15 small, 3 medium), RAW Toilet (3 small), Sweet Escapes Country Toilet (3 small), The Ambassador (3 small), The In-House Outhouse (5 small, 1 medium), Throne of Thrones (9 small)
Cats & Dogs
The Copper Stopper (10 small)
City Living
The Critical Throne (3 small)
Get Famous
The Swan Throne (5 small)
Get To Work
Cold Steel (15 small, 3 medium)
Seasons
Ain't That A Slate Toilet (5 small)
Eco Lifestyle
The See-Thru Loo (2 small)
Realm of Magic
Portal Potty (2 small)
Vampires
Old Fashioned High Tank Toilet (17 small, 4 medium)
Tiny Living
Compact Lavatory by Whenugougo Industries (3 small)