There are lots of good options all over Disney.
You do not have to eat a burger or dogs unless you want to.
They have some really nice salads at sunshine seasons.
Roasted beets and goat cheese or seared tuna for example.
Norway has really nice black forest ham sandwiches on a nutty wheat bread.
Main street bakery in MK has healthy sandwiches as well.
There is starring roles at DHS. The Black forest ham on focaccia is excellent.
You can get roasted chicken at flame tree and cosmic rays ( I think).
Other thing to consider: Bottled water instead of soda or diet soda.
The desserts at a lot of the places are really good, but you can always ask for an second bottle of water for dessert. Some paces will do that.
IF the dessert is not great have a bite and don’t eat it. If it does not look good don’t even order it it, there are lots of good desserts at the QSDP places though.
The other thing you can consider is do a lot of extra walking if you can.
For example I would walk around the world showcase once before and after each meal at epcot.
You can walk from Epcot to DHS.
If you’re at a Boardwalk area hotel you can walk to Epcot or DHS. It is faster than the boat for me.
I even walked from the Dolphin through Epcot to the monorail to go to MK.
I know not everyone is the same and not everyone can do the extra walking, but for me it helped a lot.
I ate a lot of desserts, snacks and alcohol at the F&W festival etc and still only gained a couple of pounds after 10 nights on QSDP.