I'm gonna try the 25 W vs dimmer switch.
Percolation are you suggesting the 25 W for ALL lava/glitter lamps or just ones
that have been re-done with gookits?
I like using 25W lamps in place of 40W. The heat produced in the end is equal to the wattage of lamp, but the light output is an exponential function. Dimmed to half the brightness, the power consumption is about 75%, so the lamp is getting 3/4 the heat while the brightness went down to half. The 25W bulb produces 62% heat, and provides about 62% brightness and the color remains the same.
Dimming causes the lumen output to decay dramatically and shifts the color temperature lower (undimmed is ~2900 to 3000K)
Dimmer is fine for fine tuning, but lower wattage lamp provides holds the same color temperature and brightness loss is roughly proportional to wattage drop, not more.