That enchant for warrior actually doesn't benefit AD junglers as much as the current AD jungle item because they aren't building crit chance and attack speed. It only benefits ADC's/Marksmen.
The only real comparison you can make is Deathcap for AP scaling. And if you remove Deathcap for this new item, Mages would be in a tough spot because they would NEED Smite to be as effective as they were before. The difference is that there was not an item before Cinderhulk that gave % hp scaling.... oh wait. The old Spirit of the Ancient Golem that built out of Quill Coat also had %health scaling. 25% to be exact. The only difference was that it didn't benefit toplaners as heavily because the Quill Coat only affected jungle creeps. The same thing can be applied to this Cinderhulk in some way. It needs to still do damage to jungle monsters, but it can have reduced damage to champions. This would make Sunfire more appealing to Top laners than Cinderhulk even if it doesn't have % HP. The reason % HP scaling on a jungle item makes sense is that it allows the Tank Jungler to keep up with other lanes with their lower income as they play for the lategame. Tank junglers are unlike other junglers as they are not able to pressure lanes as effectively as other junglers are. But they make up for this by having a stronger late game than fighters. The problem was that many tank junglers were unable to get tanky enough to be effective in teamfights due to their lower income. Cinderhulk allows tank junglers to be a threat in later teamfights which is what a Tank should be.
I do think some attention needs to be given to Magus enchant, but I'm not sure if scaling AP is what needs to happen. Even if this is implemented, it would be unique and Deathcap would not be removed so laners would opt for Deathcap anyway. A lot of people think that it is an issue of Magus users needing to use abilities to clear at all, whereas fighters have AAs and Tanks now have Immolate. When using abilities on magus users, it costs mana and CDs so the obvious Jungle enchant should give mana sustain and CDR with some AP to make it worthwhile.
As I said. Warrior is fine right now; it gives all the stats that allow fighters to output earlygame pressure. Giving critchance and taking away CDR and Armor Pen would actually hurt them.