Probably the best drop in LEDs are LUX, Then here are the HID angel eyes (as per my car and MFKN3's) which are the brightest. If it helps I have a set here of AngeliBright which were fitted before the HID's I had to modify the wiring loom on these to make them work properly. They are going to give you around the same as LUX which you would have to bring in. If you want to give them a try out you are welcome. They are just sitting here.
I think there is nothing better or advanced than OSS design which is going to be my next project. It is a big job though and means sending the headlights to Florida USA
Nothing is really available locally, replacing the H8s with whiter bulbs and brighter ones will most likely cook the lights and is an option I would stay away from as they are generally 55 watts instead of 35 watts.