FWIW, the Universal Sovereignty Issue is not unique or novel to the JWs: they didn't come up with the idea, but it's been around for thousands of years in apocryphal Judeo-Christian writings.
Syme said-
The official doctrine of the Watchtower is that God can destroy Satan but doesn't want to, for the time being (meaning, for the past 6,000 years). So, how can he be benevolent?
PON said-
The very fact that we question it all proves it's a load of crap. If it made sense and was obvious there'd be no questions.
Ahhh, but that's the rub, the point some are overlooking:
Per JWs, the humans who say God fails on the all-loving trait are the same individuals destined for destruction, defined as 'evil ones' who've fallen under Satan's influence! The 'evil ones' cannot be (and don't need to be) convinced of God's all-loving trait, since Xians believe God cannot allow a few hard-headed foot-draggers to interfere with the Divine master plan, so He'll just wipe them out.
So each person is essentially forced to choose between complying with God's will or take the highway to Eternal destruction with Satan and his minions (who also balk at God's all-loving trait). That's the work of 'separating the sheep from the goats', and the goats will never consent to being labelled a goat or accept the omnibenevolence claim: in fact, by pointing out how God fails to be all-loving, in the eyes of a JW, such persons are only certifying their own death warrants. self-identifying as being worthy of destruction...
That's the problem of getting into theology/theodicy (presuppositional apolegetics): once you get past the presupposition of accepting God's existence without any evidence, the rest of theology and theodicy actually offers an answer which makes sense to believers, since apolegetists have over a thousand years' head-start to 'shot-gun' multiple answers and work out the kinks.