I installed Cibie H4 lens (E-code) with 55/60W H4 bulbs. These lens have a longer (higher) cut off on the right to allow you see further and not blind on-coming traffic on low beams. The high beams really shine far down the road.
To get brighter light without going to 80W or more bulbs, you need to replace all wiring to each headlight with thicker wire ( iused 12 gauge), install two relays (one for low beam and a second for high beam), and feed power to these two relays (directly) from the alternator / battery. This set up also saves your existing headlight switch (and dimmer switch) from higher electrical loads incurred by the higher watt bulbs. If you go with 80W bulbs, you can drastically shorten the life of your existing wires and switches due to the higher electical load (amps), and not get the perfromance you are seeking. I purchased all the parts I needed several years ago from
www.danielsternlighting.com. This is a great site to learn a lot about headlights. I checked and the site still looks active.