I believe with a draw length of 28.5”, your setup should work fine with the changes I mentioned without worrying about tuning issues. It is a mistake to worry about tuning before you have developed basic form, because changes in your form will change your tune.
Equipment is all a matter of personal preference. Most people who shoot 3 under use a tab, although some use a glove. Make sure the tab is not too big, or if you use a glove, that it fits snugly. 3 under shooters should put a nock under the arrow as well as over it. Most trad shooters prefer to tie on their own string nocks rather than using crimped on brass nocks.
Their are 4 types of quivers in common use: bow quiver, hip quiver, back quiver, and side quiver. Most serious hunters use bow quivers. The problem with bow quivers is that they are awkward to use when practicing or in a tournament. Serious bow hunters don't care, as all their practice and tournaments are primarily to prepare for hunting, so they want to use all the same gear they will use to hunt. I hunt, but I am more serious about 3D tournaments, so I use a hip quiver that attaches to my belt, as it is the most convenient way to carry arrows in a tournament. When I hunt I use a Safari Tuff side quiver, as it keeps my arrows quiet and dry and hides them from view. I don't use a bow quiver for the same reason serious hunters never shoot without one on the bow: having one on the bow affects the way a bow balances and feels, so it should either be always on or always off. I've tried to love a back quiver, because it is so traditional, but I just don't. All the back quivers I’ve tried to love do work well to hold my extra arrows at home, however.
Another thing I should have mentioned before is that if personal instruction is not an option, you should consider sending in a video for Arne Moe to evaluate. He is an excellent, level 4 instructor, and has helped countless people here in the past.
Your post was a mixture of form and equipment related questions, so I chose to deal with both here in the shooting form forum. However, in the future you will get better responses to equipment related questions in PowWow.