Just run a lot of ion thrusters in parallel to get your thrust. They're tiny, that's feasible for any ship trying to go further than Mars/Venus.

Adding more of them doesn’t meaningfully change the very low thrust to weight ratio, which is what makes it hard to get to closer places quickly.

You still need to get rid of excess heat, which scales linearly with power. The more engines, the bigger the radiators you need to carry, which will increase your total mass.

This works to a degree - each thruster weights something and has cooling requirement. Also wear and tear if you run them preatty much continuously.

> This works to a degree - each thruster weights something

A lot less than the fuel for chemical or propellant for nuclear thermal, though

> and has cooling requirement.

That's for the electricity generation, not the thrusters

> Also wear and tear if you run them preatty much continuously.

The whole point of using thrusters is to run them continuously. No moving parts.

IIRC some ion thrusters experience grid erosion over very long runs - stuff can wear out even without moving parts.