Once you understand how the tool-less tank caps work they should not bring problems. There is a proper way to insert them. They are indexed and need to line up with their mating "thread" or insertion opening in the tank then twist the bail 1/4 turn. If you don't get the cap properly positioned in the tank opening before twisting the bail, the cap will appear seated and the cap will "index" as you twist the bail however the lock mechanism won't be engaged in the tank opening and the cap will fall off. Look at the cap position before you pull it out of the hole then put it back into the opening in the same position and all is okay. Some people have a tendency to turn the cap as they put into the tank from old habits of screw in caps and then it won't be positioned properly. Instead just stick it in the hole in its proper position and give the bail a twist.
The Easy2Start feature is designed for "occaisional use" products for around the home (trimmers, hand held blowers, small chain saws) for those that don't wish to exert (or have) a strong arm to pull the starter rope. You can, but don't have to pull the rope to its full length. Instead you can give it a few short pulls to wind the "starting" spring until the engine turns over.
The QCA (Quick Chain Adjuster) was designed for "non-seasoned" chain saw users who may not necessarily always adjust the chain properly as it gets loose. The QCA helps simplify the task for those that may be mechanically challenged or just want an easier way to do things.
