Oh gosh that banana couch! 😂 It gives me inflatable banana in the ocean vibes from vacations (if they offer you a ride on the inflatable banana always say no! 🌊) That sofa would be great in a kids room.
The yellow sofa in image 2 can be achieved with the large rounded sectional corner pieces from DHD and the throw pillows from Decorations (if you completed the Happy at Home Login Event where they were a reward) and it's even available in yellow, but it takes a lot of patience and the move objects cheat to place the throw pillows perfectly on the rounded shape. I like the sofa in the image more though as it goes all the way to the floor, whereas the DHD sectional sofas have legs. It's actually a nice look to place sectional seating in a rounded wall section using the DHD round pieces. I've made a few little rounded seating nooks this way but again, patience, MOO and this face 😠.
Image 4 is more like the DHD ones and that look can be achieved, but the thing I find lacking in the DHD pieces is the textures. In Sims 3 Pets ( I played the console version) we had sectional sofas but we could design our own patterns with the colour wheel and it had textures too. We had leather, fur, corduroy, velvet, whicker, suede effects and that's what's missing for me. I actually got the idea for my own home IRL and after wanting some for years I got Silver Whicker sectional pieces with footstool and table pieces and fluffy cushions and throws (it was fun assembling that alone in lockdown...5 hours and wished I could just click a few buttons on my Xbox controller 😆). I wish we could place fluffy throws on sofas in the Sims 4 too like the ones on the Snowy Escape seating. The DHD sofa pieces have a quilted fabric look and a buttoned look but that's it and it gets a bit samey despite the 2 sets and the variations in shapes. B&H introduced various (non sectional) seating with a nice brown suede effect and that's the kind of sectional sofa I'd like to see, with that cozy texture like the first image.
I'm a builder so always want more stuff! This would make a great kit idea IMO.