I am glad I can give you hope, Eric. You seem like a fit and healthy guy to start with and that also is great to have going into life with a J pouch. I learned the gas trick, too, but do it while lying down and doing a type of "bridge pose" for yoga, which is to be on your back with knees bent and feet on the floor/bed and lift your butt up so it is above your chest. This lets any stool flow with gravity back down to the sm intestine and lets the gas come up to the anus, where it can be expelled. (Sorry to be so graphic, but thought it would help explain and visualize). This minimizes the chance that you will have an accident while expelling gas.
Honestly, I think gas causes the most problems for people with a J pouch, because as you said, in public we cannot be doing these contortions! I try to figure out what causes the most gas to me and avoid it, which is why I follow the low FODMAP diet. I don't normally drink carbonated drinks but make an exception for beer!!!! Also, I drink hot water/warm water throughout the day and that is really soothing to my gut overall and helps hydrate me. You could probably do mint tea if you find plain hot water as boring as most people do. (Mint has a soothing affect on the bowels.)
As for pouch emptying, it is not a problem I have, but I remember my GI doctor talked about getting a little step like they sell for toddlers to reach the sink for handwashing. She said to put in in front of the toilet and put my feet on it while I am sitting on the toilet. This raises the legs a bit and gets the body in more of a "squatting" position to facilitate emptying the J pouch.BTW, it is recommended for people WITH colons, too, because modern day toilets are really not ideal for complete bowel-emptying.
When I feel down about my J pouch or just super irritated (because of the bathroom trips, loose stools, the sleep interruption, and all of the toilet cleaning I have to do), I try to remind myself that there are lots of people WITH their colons who also struggle. Mostly, I try not to focus on the irritations because you can get stuck there and ruminate in an unhappy state. I try to remind myself to vent if I need to and then move on! I know that irritation is not the same as the underlying depression you have, so please do not think I am equating them and telling you that you are not trying hard enough to have a positive attitude. I know that what you have is a medical condition and really feel for you, because that makes life more challenging, especially struggling to adapt to a new way of life.
I wish you well and don't hesitate to post to this group or reach out to any of us if you have questions. I still have tons of questions, even after 11 years of "J pouching"!