There is no other 'good' option for high current without using a transformer. Other options are little risky or inefficient. If you use simple resistor as voltage divider, then around 50W to 75W resistors are required, which are larger in size and cost in respect to transformers...
You can use small smps circuits as they use small transformer for high frequency. They will consume a little less space.
Another thing you can do is using a high current triac from AC line, adjust it to minimum voltage, then rectify & filter properly to get a high current output... Some triacs are BT136, BTA40 series, etc. Proper heat sinking is required...