Thanks for your reply. For this specific game I actually started with a gold chest boost from my inventory; starting with 400 extra swaps on the initial round seemed really powerful; more powerful than starting with an actual gold defense, because 400 swaps can get you multiple gold defenses. Starting with a gold chest is especially powerful if you then can combine in-game chests to get another gold chest after about 350 swaps.
Can I ask for a new gold chest instead of the gold ballista? :)