I would offer that starter kits are a waste of money if you have any background experience and parts.
if you have no pile of resisrtors and wires and such, then the kit would be helpful.
what is really missing is an ACTUAL starter kit for a purpose.
if you want to focus on gardens, the more on the water valve, soil sensor, light sensor, etc
for a line following robot ?
for sound / music ?
as for your needs, you need to know what you are going to use.
the inflatable lung or plastic bag, needs to have both a pressure soruce to inflate, and some means to deflate.
speed of both is key
noise is important.
so, the mechanics of what you want are important.
if you take two bags, connect with a hose...
set a box on on, the air moves to the other.
if you can pull the other apart (think bellows)
it would suck the air out of the first (deflate)
so, one as control, the other as effect.
getting a souce of compressed air, then shooting it into a bag can be noisy
getting the air out can also be very hard to do.
using an Arduino for either is really a beginner level thing, so it is a good choice as a first project.
mechanically speaking, you have more work to figure it out.