Dave,
While some balls can be sensitive to oil, usually it's the combination of the ball, your release and the drilling that makes them "over/under" on any pattern, even when the pattern seems to be a wet/dry one.
The Enriched U is a super low RG ball with older, fairly hard Brunswick particles even though the ball is a pearlized one. Either your release or the drilling might be making the ball "over/under".
Many balls can be made less sensitive to such using lower pin drillings, such as the Rico. Mnay times even a low pin with the MB/CG moved towards the VAL will help the ball a lot.
Surface is also an important factor. Changing polished pearls to 4000 grit Abralon, lets them handle the same amount of oil as their polished states, but makes them much smoother and allows them to handle wet/dry and carrydown much better.
That said, a ball like the Visionary Gladiator Pearl or some milder solids like the AMF Villain or the Brunswick Avalanche Solid would be much better choices than the Smash ZOne, Kinetic Pearl or Tantrum. The Smash Zone is smooth for a pearl, but much less smooth and even than the Gladiator Pearl. The Kinetic Pearl and the Tantrum are more flippy than your EU, in general.
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