That list looks ok, although the black widow solid isn't an oil ball for everyone. The black widow bite might be worth a peep if you like that line, same shape, but more as far as I've gathered, especially with your low revs.
In that bunch, I'd have a particle ball, as they're always useful to have around, so I'd switch either the BW pearl for a sidewinder (long pin with polish) or the ultra zone for an impulse zone (my fave ball right now) if you can find one.

Despite my comments, you appear to have achieved your aim of a skid-snap and an arcer in each category
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Reporting from England

This is mine:

Cell
Black Widow
Black Widow Pearl
Pluto
Blue Hammer
Plastic
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Formerly SGC300
"Never get into a pissing match with a skunk, cuz he'll piss all over you and like it."-Keyshawn Johnson on Terrell Owens

Here's mine:

Roto Grip Epic Odyssey
MoRich Awesome Revs
Hammer No Mercy Beat'n
Hammer No Mercy
Ebonite Angular One
Hammer Blue Vibe
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MainePBA
"Power tends to corrupt; absolute power corrupts absolutely." Lord Acton