Sanity check: Routing high current traces (MOSFET relay circuit for 300W heater)?
If you can i'd move the input connector to next to the output one, since the input_1 trace can go directly between the two. That'll shorten the trace lengths between the connectors and to and from the MOSFET. I'd also copy the traces to the front and back of the PCB to maximise the copper carrying current and look at necking down the traces a little less (depending on what the board house can manage).

If you're copying the traces to the front and back of the PCB then you don't really have to take any chances with minimising clearance. One final tip for this kind of situation is staggering the drain and source pins so they can be necked down less but this is trade off between between the gain and current loop area by having to stand the MOSFET further away form the PCB to do it.