I feel with dual wielding pistols being able to shoot same target twice for burst fire or shoot 2 targets 1 time each is enough to justify a slower reload time, on top of not having the +12 acc from single wield, I wouldn't say make it twice as long to reload but maybe something like 1.5x the reload speed of a single pistol.
Kinda just want single wield pistol to be able to load faster, I would take that over +12 acc if I had to