It's actually a good step up for AJ. But in all honesty, AJ hasnt shown any sort of drawing capability, so IMO, Briggs would be more inclined to fight Fury if he were gonna make a big fight outside of a title fight. While I figure KJ would beat Briggs over 12 behind his Holmes-esque jab, he's still a very defensive fighter when it comes to taking shots. He's got a granite beard, but he shells up offensively when he's put on the back foot. AJ will put him there quickly, and he'll likely be the first to stop Kevin Johnson via Brittish stoppage....(beaten, maybe even down, but not hurt badly or out by any means.) Whereas vs Briggs, there would actually be punches with bad intentions actually coming back at AJ, and in that manner.....it would be a step up for Joshua. Briggs would also make a nice comeback opponent for Chisora or even Helenius.
It would be a small step up. At his stage I honestly don't think Briggs is much better than Sprott, he's that shot. Briggs has been facing stiffs that even Wilder wouldn't face now. Love took him the distance and Love the year before lost to a guy with a 7-6 record. The fact Briggs has been facing such dire opposition and still looked awful says a lot about how poor Briggs is now. He was shot when he fought Vitali and that beating utterly ruined him. Both Chisora and Helenius would give him a one sided beating.
AJ from what I've seen has shaky D. Bahktov was able to land some punches not because he was creating the openings but AJ was giving them to him. If he gives Briggs those openings and he gets clipped, he could be knocked out...esp if his question mark turns out to be glass. Briggs is shot but he's big and strong from years of weight training and steroid abuse and can still punch hard. Not a probable scenario but a one that is possible.