These cards while fine, are the weakest links in the deck or don't synergize well enough that are the best choices to cut
Secret Lair is now just as much a lottery as opening boosters
Ultimately if you are getting cards graded, you will want to be confident of getting good grades, whilst there are greater experts on the subject than myself, personally if I am paying to have a card graded and having it sent off to the states etc, I want to know that its going to grade reasonably well
Allosaurus Shepherd provides insurance against counterspells for all of our spells (even cards like Collected Company or Green Suns Zenith) while also giving us an alternate win-con by mounting all our elves onto dinosaurs and mauling our opponent
Zahur shines in aggressive sacrifice decks that snowball once the engines start running
Meanwhile, Tidus, Blitzball Star is unfortunately the worst multicolor uncommon in the set