The horizontal bars are important for climbing exercise. Your Budgies will climb and slide and walk on the inside top of the cage. We like to concentrate toys at the top 1/3rd and leave the lower areas for wing exercise. We put toys all over top and bottom, but make the toys feel like tree leaves to hide behind at the top. Soft rope perch at the top area so the place to sleep and give feet a brake. Watch and check for red sore underside of the feet. Important to have two large doors to service the cage and small doors for food. A floor grate , movable to clean and a slide out tray to clean and replace debris. It helps to have a mesh guard to reduce seed and feather scatter. A towel on back and sides and part of top will reduce fear of predator coming up from.
behind/overhead. Replace any soft perches where the strings are being chewed as this can form ball in crop and will not digest and is often lethal .
The perches that have a smooth surface on top and sand on side to keep nails trimed. Lava rocks are great bird fairs often have larger ones available.
We use cactus perches and well as , grape , natural branches with different thickness and hardness. Kabobs Manu roses cuttlebone , brown salt wheel,
are also good the more the better. We are trying to expose our birds to as much as possible so that they will out grow fear of the unknown . Practice
small cage transport to reduce fear of the vet. the more toys and rotation the better. Keep your birds wonder what will be next. They will be more active. Blessings, Jo Ann