When it comes to racks, don't spend hours finding KJ specific ones- it is a waste of time. Racks that fit crossbarred Xterras and full cab Tacomas will fit too. Ignore brand names and use a tape measure to determine what is right for you. Also keep in mind that the KJ is in the "prone to rollover" range of SUVs due to the narrow wheel base and mushy OE suspension. (Which is just another reason things like roof top tents are a bad idea)
A few things to remember:
The OE rails are rated to a max of 150lbs for a reason (Yes it will hold more, but this increases your rollover risk)
Most crossbars are within that weight limit too, but you have to subtract the weight of the crossbars from that.
Same with a rack or basket, that weight has to come off the max total too.
If you put stuff on the roof, are you willing to cope with the other issues this creates? (Flat racks are notoriously noisy for example)
RRO doesn't have the best reputation anywhere and yet charges Premium prices.
My advice is to be honest with yourself. Are you going for "the style" or have a need to carry gear on the roof?
As a final thought my "cheapest of Amazon special" did just fine loaded down in pretty rugged conditions and provided me with the extra storage I needed
whilst making the wife happy with what I call "instagram looks".
Now if she'd just quit making me wash the mud and dust off so often...