Intensity is nothing to do with height, as many members prefer Detonator to rides like Apocalypse or maybe Hurakan Condor in PortAventura which is over twice the height.
It's all down to the manufacturer. Detonator is manufactured by Fabbri and instead of falling under gravity, it is forced downwards by 4 pistony type things at the top (pneumatics I think), whlilst Intamin drop towers just fall under gravity.
Extremis is manufactured by ABC who have very little information on their website regarding how the ride works, but in short the intensity you feel has nothing to do with height.