The Hamster Heaven is a really good cage for a dwarf, if the house on the top and the tubes are removed.
If it doesn't come with end caps to cover the holes where the tube connects, you can buy the Ferplast ones from Porton Aquatics and put the cap on the yellow plates that come with the cage (that should make more sense when you've seen the cage in person).
FPI 4820 Wire Connection | Welcome to Porton Garden Aquatic & Pets
The green house is removable and then you have a little top door.