Every other D&D game I've played that has involved rogues with SA, it's been automated for ease of gameplay translation - that is, it applies to eligible attacks (the first one per turn in editions where it's limited) automatically, but it does give a notifier that you're getting it, more than just a damage number (NWN for example, gives you a little grey text notifier of 'sneak attack' whenever the damage applies').
As it is now, it's a ridiculous implementation that detracts from the rogue class as a whole. They could automate it, sure; it wouldn't be quite as flexible as table-top, but it's what most games do. They could also make it a toggle, since they seem to like those off on the right side of our bar - when enabled applies it on any eligible attack, and when off, does not. That would grant almost the full tabletop flexibility with only the weight of one extra click, on the occasion that you don't want to apply it to your first attack, which is not *very* common.
Either choice would be light years better a choice than the current iteration.
