Pioneer seems perfect for the slow-blue-nonsense decks that want random Lightning Bolts and land redraws on turns twelve through fifteen
If a card is discarded while Rest in Peace is on the battlefield, abilities that function when a card is discarded (such as madness) still work, even though that card never reaches a graveyard
Kormus Bell which turned all Swamps into 1/1 creatures, Tawnoss Wand which made your creatures with power less than 2 unblockable, Tetravus a 4/4 flying creator of 1/1 flyers and Triskelion a 4/4 that could deal limited direct damage were all removed from the play set as well after Fourth Edition
If a creature in combat has banding, its controller assigns damage for creatures blocking or blocked by it
Thankfully, a Simic deck would have plenty of options in this regard, even in Alchemy
All-in-all, considering anti-Goad tech is quite rare, and the cost of running Serene Sleuth is rather minimal, I quite like this card