This card is a great Lockdown-preventer (people using Horus will despise it), but it can also be used with other lockdown cards that you control yourself, such as "Royal Decree" and "Sky Scourge Invicil"- your Spells and Traps will not be affected by them. Note that "Jinzo" and "Spell Canceller" do not work with "Splendid Venus". While "Splendid Venus's" effect states that "the activation and effects of your Spell and Trap cards cannot be negated", Spell Canceller and Jinzo simply prevent the activation of Spell and Trap cards rather than negating the activations.
"Magic Drain" is a great card to use with this card. If your opponent discards a Spell card they would negate "Magic Drain" but "Splendid Venus" prevents negation. So whatever Spell card they activated would be negated with "Magic Drain's" effect.