What do you have in there specifically? In my experience the only thing my guinea pigs absolutely need are the following:
1. Hay
2. Pellets
3. Veggies
4. Hidey Houses
5. Bedding
6. Water bottle
I obviously have some other stuff in there like tunnels and stuff. I also own a midwest cage and I'll just tell you that my guinea pigs never play with her toys she just likes running laps around her cage, sleeping, and eating. It looks like you have a lot of hay in the picture maybe remove a little bit.