From: OH, USA
Your best bet is #3, or #4 after AGS splits in November (?) '42.
My general setup for 1942 is 1) removal of german corps from army command chain wherever possible and to place these (in order of available space and proximity for leader rolls), under Finnish army/high command, AGN, which tends to have some space), and then OKH. This costs 16-18 AP, and if you plan ahead, you can take some infantry divisions with them. Specifically in tight fighting sections such as Moscow and the north, I place 12 or so divisions DIRECTLY under army command under my best generals (Model, Rendulic, some other infantry 8's; Guderian, Manstein; the latter can use some infantry if pushing in close proximity to them too). This is because their awesome ratings perform better than if basically any other corps commander was under them. This setup frees up 10-20 Corps to put extra reinforcements and, importantly, axis minor allies under. The average German commander (4-5 morale and infantry ratings) is equivalent to the best AMA commanders, and you have plenty of 6-7 ratings to go around using autopromotion. AMA support units are pretty much worthless until the defense stage of the war, and even then, contribute only minor CV. You should have enough AP for this in 1942.
These freed up corps can be used to push Crimea under a unified command structure. On the other hand, you could even take an entire army (6/11/17), and do what I mentioned above. You can also have one or two corps (or more!) to load up on the heavy artillery to support the main attack on Sevastopol. For example, you can have all 3-5 heavy howitzers/guns and the remainder 6 slots per command used by the M18/K18 guns with good artillery value, getting you a bonus 400-800 or so engineering/artillery value while attacking Sevastopol.