There's a few extras in the pic that I may bring, like a coffee thermos for short hikes on cold days, YAKTRAX spikes in case it's icey, and a headlamp.
I haven't tried SOTA yet but I really want to get into it. If you're bringing the pack, does the water bottle holder go into the pack with the gear in it, or is it carried separately or attached to the outside of the pack?
Short easy hike? I'll bring the KX3 and amplifier. Long hike? Just the MTR3B and lightweight antenna. Crowded or densely wooded summit? I'll bring an antenna with a small footprint. Having options is nice.
And of course all the jackets, water, food, and other stuff one needs to be safe in the woods.