I was thinking of getting one of these along with the argos one.

Scratching Post for Cats by Cat Walk-Activity centres-Pets at Home: Buy Pet Supplies from our Online UK Pet Shop

Viana 44cm Cat Tree Activity Center Scratcher: Amazon.co.uk: Garden & Outdoors

& one of these activity trees
Cat Tree La Digue on sale now at zooplus

Cat Tree Oviedo: Great Deals on Cat Trees at zooplus

One of these:
Two Tier Cat Basket, Light Oak: Amazon.co.uk: Garden & Outdoors

1 of these 2 (bottom one goes with my living room!
Cuddle Den Minou: Great Deals on Cat Dens & Cat Beds at zooplus

Black Faux Leather Sofa Cat Bed by Pets at Home-Beds-Pets at Home: Buy Pet Supplies from our Online UK Pet Shop

one of these litter trays:
Deluxe Hooded Cat Litter Tray by Marchioro-Litter trays-Pets at Home: Buy Pet Supplies from our Online UK Pet Shop

Great Deals on Litter Boxes & Cat Supplies at zooplus: Corner Cat Toilet House with Filter

food bowls?
Buy Ferplast Duo Feed 03 Grey Bowl Holder Cat Bowls

will also get those toys you mentioned.

What do you think of these items?:
Sisal Roller Scratching Cat Toy Playing Claw Furniture: Amazon.co.uk: Garden & Outdoors

Corner Wall Cat Scratching Post Playing Claw Furniture: Amazon.co.uk: Garden & Outdoors

Snacky Food Ball Toy For Cats, Cat: Amazon.co.uk: Garden & Outdoors

I will also need a grooming kit.

What do you think?