The Trap Expert feat is for quicker arming/disarming of traps, and increased detection difficulty.
This is nice for those who like to prepare the battlefield with traps, but in no way essential. There are so many competing feats that are good.
However, a trapper character with decent dexterity and agility (good stealth) who could potentially have a use for Trap Expert, is unlikely to have high strength, and traps are heavy!
Suggestion is to make Trap Expert halve the weight of trap utilities in addition to what it already does, as you are an expert of handling them.
Ex, bear traps: 1 -> 0,5 kg, mines 2 -> 1 kg.
This does not alter the playing mechanics in any way, but enables you to carry twice the amount of traps, so you can actually be a trap expert in practice.