Hi! Taste in pickups is different for everyone. So it will be hard to suggest one.
I haven't tried a JB jr but I do have a JB humbucker in my jagstang and really like it. I would describe it as a good middle of the road pickup. (Pretty good clean and pretty decent distorted)
I have a strat with a SD hotrail which is great for distortion but not so much for warm cleans.
Did you like the Antiquity 2? Or looking for a different type of sound?