haiku retrospective clx

A haiku master complained about the ho-humness of this haiku:

old gym shoes --
the echo of the bounce
inside the ball

I heard the bounce echo in my son's freshly-inflated Gertie ball and suddenly I had 2/3 of a haiku (she's working with 2/3 of a haiku, folks), so I started casting about for a first line. I immediately thought of:

distant thunder --
the echo of the bounce
inside the ball

This seemed overdone in a metaphorical sense (the echo of the bounce
might sound like distant thunder, but the comparison would make a
tawdry haiku, IMO).

Next up was sultry evening. I first typed it like this:

sultry evening --
the echo of the bounce
inside the ball

This is the story of my haiku life. I really would appreciate
some hints on finding good opening images.

lighted fishtank --
the echo of the bounce
inside the ball

last dance --
the echo of the bounce
inside the ball

weaving drunks --
the echo of the bounce
inside the ball

empty bathtub --
the echo of the bounce
inside the ball

sidewalk chalk --
the echo of the bounce
inside the ball

mosquitoes whine --
the echo of the bounce
inside the ball

loaded derringer --
the echo of the bounce
inside the ball

symphony program --
the echo of the bounce
inside the ball

But I like the gym shoes. They were right there against the Gertie ball: Dad's old shoes and his sons' new ball. I didn't deliberately make a connection to basketball although it's likely that I was doing so subconsciously.

Here's another question: How much separation does there need to be to juxtapose two images? Can you sometimes have related images or is it important that the juxtaposed things always be a mismatched set?