things like intercooler piping diameter, boost threshold, AR ratio will all make a difference for your lag.

Torque is pretty much not going to happen. Wouldnt longer intake runners increase torque in theory? I guess you could turn up the boost more.

For the lag a small shot could spool that turbo up quicker as well...

I'd just get a larger engine if thats an option. 1.6l turbo is tough.