If she's bar chewing at the moment it's uncertain whether that will stop if you move her to another barred cage. The rule of thumb I find is that they don't bar chew in anything 100cm or bigger. There's actually been research on that. But there are exceptions. They can still bar chew in an 80cm hamster heaven. The Plaza is basically the same size as the hamster heaven but 20cm longer. So it's the width. It sits well on top of a chest of drawers for example. It doesn't matter if there's some overhang.
I also wanted to add that if you got the cage from a well known pet shop, people have returned them for a refund saying it's not big enough for the hamster. Even after getting the new cage (you need another cage obviously before you take the first one back). Even though it's been used.
How old is your daughter? It's nice she wants to have Zazu in her room - it could be an idea to try and hamsterproof her room in case she gets out again! Ie just make sure there are no holes in the skirting board or floor where pipes come up and if so block them off.
There are some larger tank style cages but then it's space again. One option, if you have space in another room, is to have the hamster in there, and your daughter can take her to her room for out of cage time and play time. You just transport them in something safe - they will often just hop into a hamster ball and you can pop the lid on and carry the hamster ball to where you want to let them out and then set it down and take the lid off. Hamster balls aren't really recommended for use as a ball though as they're too small and too risky with accidents.
The detolf idea somebody mentioned would be good, if you have space for that in another room - it can actually be quite a nice thing to look at in a room as well, if it's stood on top of Kallax units which provide a lot of storage underneath too. Except with that there is some diy involved as it needs a lid making out of wood and mesh.
There's the maxi duna multi which is a perspex tank style. It's the same size as the Savic Plaza at 100cm but easier to manage. I'm not sure if it would quite give enough enrichment for an active syrian though.
What was it about the hamster heaven that appealed to your daughter? Was it the colourful contents etc? There are ways you can be quite creative that are fun, to make a plain cage just as fun and colourful.
If you have a look at these two threads it might give some inspiration

They show other peoples set up ideas and also things that people make for toys for hamsters, that don't cost much and it's fun to do. It can become a hobby in itself!
www.thehamsterforum.com
This is a thread to show how many things you can make for your hamster or enclosure, out of cardboard :-) Cardboard is your friend.
www.thehamsterforum.com