Thank you, Wolf and Pajarita!
Joy is the one in the front, Penny is now around 2,5 years old and fully colored, while Joy who is only 6 months hasn't had her colours fully developed yet. She gets more blue (colourwise!) every day though, it's a joy (hehe) to watch her grow and mature!
Also thank you for the note regarding the strings on their playtree. I always supervise their playtime but the plan is to find a better solution, if I could find some stainless steel screws and borrow a screwdriver I might attack the perches onto the tree that way instead. The bigger sisal rope you see is very loosely attached and mostly for them to chew on and play with, they can pull it loose themselves if they wish to (and they do so regularly), so that one should be fine. The small ones though aren't great, but I've deemed them safe enough as a preliminary solution when the birds play under my supervision
I also have two other playtrees for them but they're currently under reconstruction as they weren't very well balanced. They never fell over but they swayed disturbingly when the birds landed on them... :/