I started with a UnitiQute, added a 250 to it. Then I got a NAC202, dumped the Qute, and replaced it with a ND5 XS.
You might want to put your wallet under lock and key now, before it's too late.
But to answer your question, adding a 250 to a UnitLite will certainly provide a great power section for the Focus 160, although I think the 200 (at half the retail) might be a better bang for the buck. In any case, the UnitiLite alone should do quite well with the Focus 160 for all but the most demanding situations.