SmartTube is even better than that: it lets you select from a huge range of speeds (I frequently like 1.25x and 1.5x personally, but it has even more fine-grained settings like 1.15x, 1.20x, etc.), and it remembers that selection for that channel, so if a particular Youtuber is a slow talker, you can pick a speed that works well and all his videos will show at that same speed.