Have been using cheapo c6 for 6 months but hard to judge because less travel during mco. Brighter than halogen. Get the yellow light

Just change to Osram NB Laser or Philip XV +130 and be done with it.

you want brightness or you want looks?

brightness some of the official way is to use Osram Nightbreaker series or the philips equivalent, as per speedy3210 said

though these "better" bulbs would have shorter life time, some up to 1/3 your default bulb

mine last 1 year or so with 8k -ish drive

if you really want brighter bulb, do the H9 modification to fit H11
without the glare cap and higher wattage (65W vs 55W) it will be brighter, but can cause glaring

Colour temp (4300K , 6000K) does not mean brighter
just yellow vs white colour perceived by the eyes

it has been said that white light (5000k and above) have trouble in rainy or foggy situations
while yellow penetrates better and give better definition in these poor visibility conditions

though recent development of the LED bulb does indeed give better light output (Lumens) there is still the problem using LED in a reflector type headlamp.
this is due to unable to have the lighting element (in this case, the LED chip) be thin and small enuff to be in the exact same location as the  filament in a normal bulb

so the light output would have slight offset and can create hotspot/shadow

also be wary of LED with great putput initially, but fizzle out over time due to heat
units with active cooling would suffer greatly if to say the fan malfunction, or even reduced performance in cooling over time

one benefit of LED is the perceived longer lifetime
but this would be negated if to say the later half of the bulb life, it shone less bright than when it was new

TS, is your car tinted? Maybe the tint too dark.
Philips ZES is good. Bright and low power.

If use LED bulb, make sure to set the lamp height correctly.
When done, stand in front your own car with the lights on make sure you don't punish other drivers.

Correct.. if existing is halogen headlamp, either reflector or projector, go with halogen bulb. Cheap and almost standard price.

A lot of low quality aftermarket led bulb and sell to people that wish to have a change. Basically burn your pocket money for no reason..