I usually bivy hunt and prefer using two packs also. The larger pack on my back is stashed in a somewhat convenient spot so I can return to it every 3-5 days and restock on food. If the weather looks like it will hold out, I hunt with a bivy sack and leave a small tent in the stashed pack. If it looks like I’m in for a long stretch of bad weather I trade out the bivy sack for the tent. I also use the larger pack to haul large loads of meat out. The smaller pack is the one I carry when hunting.
The tent may add weight going in but its worth bringing along. I’ve slept in a bivy sack during many rainy and snowy nights. You don’t sleep well in a bivy in those conditons which takes its toll on your hunting during the day. I talked myself out of taking a tent on this hunt and it rained almost every night.