160 is definately better than 96!
if you wanted to get as much light as possible over that tank, without going for halides, you could either get 4 48" vho bulbs to fit over that, or you could get a hood that held 4 55 watt pc bulbs. the better of the two would be 4 vho bulbs i believe for total maximum wattage.
i was at a lfs today and they had some slim halide reflectors. looking at some possibilities for a set up for my next tank, we found that over a tank that is only 12 inches front to back, you could fit a slim reflector (only 4 inches) and 2 vho bulbs, but you need to use an insulated heat resistant material between the wood and the reflector, i would mount the reflector on posts about 1/2 inch from the barrier to give room for air circulation, and it would be a bit rishy to go for 250/400 watt halides due to the heat generation. 175's would be more than fine.
there are a number of people on ---- that sell dual 175 halides mounted on a reflector that will fit over a 55 gallon tank for around 250 dollars with bulbs. you might want to consider saving for something like that instead of buying another set of lights that will eventually need to be upgraded again when you change your list of organisms you want to keep.
on a side note, the price difference between 175 and 250 watt halides are minimal, so as long as you can take care of the heat issues, you might want to ask about the price of upgrading wattage, since a 55 is deep enough to begin making use of the higher wattage.
good luck!