Honestly the clause I believe demands the most discussion would be the Sleep clause -well, aside from the elephant in the room, Species Clause-. At the end of the day, Sleep is an extremely powerful status. So powerful, in fact, it has been likened to being equivilent to a KO. With a plethora of fast, easy sleep abusers (darkrai especially comes to mind), I'm not entirely sure that it would be a valid option to remove the clause, as what pokemon who can abuse sleep abuse it hard (Breloom, anyone?).
As for the other clauses, save species? I don't think we'll be keeping them, simply because it is A. hard to get resistances against these tacitcs without taking on a very specific, very narrow niche of pokemon, and B. they turn the entire game into a dice toss, even moreso then our usual RNG such as Scald Burns, Thunder Paralyze, etc. Being able to flat out dodge moves or get kills you otherwise couldn't is a huge, huge reward. To play with OHKO and evasion comes at a heavy cost, but do we really want to play in a game where, theoretically, someone could bullshit victory with six choice scarfed OHKO move pokemons with you being able to do jack shit about it?