Rocker vs. swing vs. rocking lounger

My mom & aunts think my registry is lacking (they're probably right, they're throwing a HUGE shower (big fam!) and lots of people will probably buy for baby.  Anyway, they all encouraged me to register for a bouncer & a swing.  Are both necessary?  What about these rocking napper things?  Necessary?!  Trying to keep the baby junk in the house to a minimum, but I also want baby (and me) to be comfortable & happy!!!