My wife is also 5'2" and I have both the adjustable pegs and the FB16 on my TG.
The FB16 let us move the floorboards up so she could use them comfortably as well as the adjustable pegs.
They also help with getting her thighs off the grab handles which I have change from the stock to a flatter set from Kuryakyn
We removed the rubber from the Kuryakyn handles after we found that it was breaking down and leaving black marks on the back of her legs.
She has the capability of selecting one of 3 options while riding and can change the adjustable pegs to another option in seconds while stopped.
Some may be able to make the change while riding but I wouldn't recommend it.
She does not have much trouble with her hips but has had her knee worked on so not quite the same as your wife, but I believe all the options I have may help.
Ride Safe
Bob