1) I don't understand how that makes more sense.

2) No Just no to all of that. And here is why:
Long range combo: We literally don't need a long range combo. If you're away from the boss for long enough to do a 3gcd ranged combo, I hate to say it, but you're not playing melee right. Even in the harder content, you only spend 1, MAYBE 2 gcd away from the boss before you can go back in safely and do your damage. Also, you're not asking for Trick Attack or Shadowfang there. Your asking for completely new abilities you wished were named "Trick Attack" and "Shadow Fang".
Chances to do things: There is a reason why AST cards got gutted in ShB, and that is because nobody likes chances, and it doesn't feel that good. And their odds of getting a "useful" buff back then were 30%. So unless the abilities guarantee a blind or a dot, they won't feel good to use at all, and aren't contributing as much as they should be. Also, Trick Attack already gives essentially a defense down to your target for 15s. It really does not need the added blindness.

3)Completely pointless because you're already behind the boss and in melee range 99% of the time. That 1% is for when you're Armor Crushing. Actually, it would cause more harm since the teleporting would just become another animation lock for us to deal with.