I'm finding it hard to remember exactly when we got DS's kitchen but it was around Audrey's age and he LOVED it. He was already used to playing in the kitchen, he had a busy box with a speaking crock pot, some toy fruit and veg, a real egg box filled with toys eggs (bought in the sale just after Easter, they are plastic craft ones that are intended to be filled with something and used on a hunt, they 'crack' open with a hinged side. Easter is just around the corner so get ready to pick some up in a sale!), a tea set with tea pot cups etc. And some regular kitchen stuff like cookie cutters, a whisk, wooden spoon etc I also popped in an empty mixed herb tub (plastic not glass) which he loved taking the lid off and sniffing the inside, it was so successful that time to time a make others with strong scent but empty pots. So I totally agree with trying her out with a small set right now. Initially DS didn't do a lot of feeding his toys (developmentally I think this came later) but he did enjoy the toys and pretend cooking, and I created a 'box monster' which he liked to feed so long as I was speaking as the monster/puppet. A bit later he started to feed his toys and baby doll. he also loves to make us all a cup of tea.
I wouldn't say he's played with it every day but most days it gets a look in.
I've extended the set (and limited it with rotating stuff) with a small shopping basket, a fabric shopping bag and some empty food cartons go in there for a while before being binned.
Just recently at 2yo he did some 'shopping' from the kitchen in his little basket, took it into the living room and used his cash till as shop keeper, then transferred all the food into the fabric bag and proudly announced he was off on a picnic
He put a blanket out on the living room floor, got a few character toys out and dished up the food.
Dolls house he was given at 12 months but I didn't get it out until I saw how much he loved the lego hospital and all the happy land houses and shops at play group. He isn't SO into the dolls house but I think it's the style of it because he does still love to play with those things at group. he does ask for it time to time, puts all the furniture in, gets his little character people to go in it etc. it's good for a day really then we put it away again.