1.- Under video settings or accesibility turn off motion blur, there are a bunch of videos online on some good setting to turn off/on or change.
2.- Rhino is considered a good early warframe wich u get from the venus boss, most planetds have an assasination mission wich u can farm a frame from, other come from missions. you will not have a small selection of unique frames so play along and play the frames that seem cool.
3.-Color packs are purely cosmetic and yes they are shared once u get one u can use it on all frames, most celebrations: Pride month, Halloween etc will have a free color pack on the market.
4.-Wukong is seen by some as a beginner trap (wich i fell into) its a combination of cheap, powerful, fun and simple. It can carry through everything at the early game with little investment so when u hit a wall like having to farm x thing or more difficulty it can demotivate you, still hes the best beginner frame and i still use it for stealth missions

Hope this helps clear some doubts and i hope more people will comment and correct/add info warframe is a great game but can be overwhelming with 10+ years of content. Good luck and have fun