1) Better cooling: non-tooth paste thermal compound, more space for heatsinks
  2) Not overdriven LEDs
  3) Introduce DC power lines (within the house/building) -   galvanic corrosion still might be an issue
  4) In lack of point 3 - more efficient AC -> DC converters, preferably with lower temp threshold, 
  having 150C default for the internal mosfet on 8pin LED driver is really high.
  4a) AC-DCs require quality passive components: coil and caps.