Will they let you add knobs to the cabinets? Maybe if you took some pictures as examples to the land lord they might change their mind about the paint. Changing the room color, painting the cabinets and adding knobs would update the kitchen a lot.

add decor to the top of all cabinets .. under cabinet led lights .. a accent rug .. I would add a accent lamp to counter top for ambiance.. and also there are magnetic decals to attach to stainless steel appliances
Like , Van Gogh starry night it literally is for attaches by magnet ( overs*ock) it looks very nice and has great reviews!

Lots of different themes to choose from as well

Clear away all clutter, take a picture, go to Benjamin Moore and run it through the computer to try different colours on the wall. Print out the pictures you like and show your landlord. Perhaps he /she can be persuaded to allow you to paint.

Don't waste your time or money. The only thing that can help. Is to get rid of the very dark dated wall color. Cabinets look bad too. A can of white cabinet paint could do wonders for them. Declutter too.