Bigger is better in terms of optics and reflectors. A small light source, optimally placed with an accurate reflector, and a proper lens will outperform a larger light source with less than optimal reflector and lens.
No matter what I did to the lights on my 1993 Caprice, they sucked hard core. I had Heliolite 80/100 bulbs, relays to boost the voltage and had polished the lenses.
I have had older Honda's with composite lights that were absolutely fantastic, Stanley has been their lighting supplier for many, many years now. My newer Civic has 9005/9006 halogens and they absolutely blow away the same bulbs in my GMT400, as far as pattern and performance per watt goes.
It really is a crap shoot what we are given by vehicle manufacturers.