Good tips.
Do whatever is the easiest for your loading. Personally, I cradle my rifle on my left side, so both the bag and the horn ride on the right.
One other thing I usually do - and I know some folks disagree - is to NOT use a thong to keep my plug attached to the horn. By using my teeth to hold the stopper whether I'm loading or priming, I have a physical reminder that I need to put the plug back in the horn. The only thing you may want to do is keep a spare plug tucked away in your pouch in case you lose it. Though I've done this for the past 5 years, and so far so good.