Push-up grips extend the movement at the bottom point, which increases the stretch in the chest. They also increase the intensity because of the way they are touched. You can also use books or bricks instead. You can get them here in the shop.
Sling trainers are an excellent addition. You can use it to train exercises for the rear shoulder like Y Flies and also the whole body. Assistance exercises for the entire body can be performed excellently with it. It’s available for 40 euros.
Resistance bands come in different strengths. Strong ones will help you with the pull-ups. You can wrap it around the bar and put your knee in at the other end. They simplify the exercises. Otherwise similar to Sling Trainer applicable.
Dumbbells and kettlebells are a good addition to the exercises. With them you can add more volume to the arms and shoulders.