Try removing the door to your toddler's room and replacing it with a swinging gate. It's better than keep the door open all the time, and the best part it can keep them in the room when you don't want them roaming the house.
Dear future me: you better be the coolest parent out there and put a slide on the stairs. definitely needs to happen into the kids playroom (basement) JESSICA SAYS: and dear future me hospital bills will be high pls don't be stupid :)
Simple stack of multiple fabric-covered foam pads. makes a cushy "sofa" in the playroom, and can be pulled apart for multiple sleepover guests, movie night pillows, or tumbling games, etc. (they have fabric covered foam mattresses at Jysk)
Tree book shelves -- great for kids room. Enticement to read. I'd like to see it made with darker wood or painted a rich brown color and placed in a living room. Also, this is full like a summer tree, I'd keep it more like late autumn with fewer displays.