[casstony]

Fork mounted alt/az is comfortable to use once it's set up, but in larger sizes can become too heavy to carry (for some).
I moved away from fork mounts to a Discmount DM-6 for my C11 which has these advantages: heaviest component is half the weight of a fork mount; no motors or Go-to to break down; silent operation (push-to); you can't get any backlash or vibration from the mount; the Discmount will never wear out. The Sky Commander pointing is simple, easy and accurate to use - older Sky Commander units were geared towards the northern hemisphere but the current model has plenty of southern stars to align with.

A tweaked dob is almost as good as the DM-6 with C11, though the dob doesn't have as much flexibility with eyepiece positioning (can rotate diagonal on C11) and I can't store a dob optical tube inside the house. The tripod of the DM-6 copes better with uneven or wet ground.

The observing chair should be adjustable in small increments to get your back and neck in the most comfortable position. I've been using a home-made Denver observing chair which is very good but not perfect - I have had the occasional fast ride to the bottom and it's a little heavy. In the lowest position it is very comfortable for power naps (hint: make the back support a few inches longer if this is important to you).

Binoviewers make it easier to look at an object for a longer period of time since both eyes are more relaxed when looking at the same thing, assuming bino's work for you - some have trouble with one eye fighting for dominance - you need to be able to relax and forget that you're using two eyes.

RID mosquito repellant on hat and clothing but nowhere near optics - nothing interrupts observing more than biting insects. It's a pleasure to be rid of the little monsters in this cold weather.

Accessory case big enough to take everything I might need to the back yard - sunglasses should I need to go back into the house for some reason.

A laser pointer is great for rough pointing of the scope and handy for checking the naked eye location of an object that you're viewing through the scope.

Some form of dew control.