I would not take away Sneak Attack from the Rogue. If you don't want to use the feature, don't use it. But I would rather have it and not need it, than need it and not have it. The various subclasses let you move your focus about, and that is what the (supposedly) Thief subclass is. If it is deficient in skill usage, fix it there - not gimp the class overall on Sneak Attack. Though, it would be nice if you could trade some of the d6 damage for inflicting conditions or doing other things.
If anything, I think it should be possible to add, specialize or otherwise muck about with skills, tools and languages as one advances to have more control over that sort of thing. The training rules to expand on that stuff as they exist are absurd and dumb from a game design point of view, and you shouldn't have to burn an ASI/Feat for that part of the game.
Similarly, I think Eldritch blast (or Hexblade option) should be baked into Warlock, rather than be a "optional" cantrip. Got a player right now who has handicapped the party because they didn't take EB, and is worthless after blowing his two spells trivially in the first couple of rounds of combat for the day.