Is the "left/right button on the bottom left and jump/action button on the bottom right" controls still the best/most comfortable option for players? Has any other game implemented something different that you think should be adopted?
Personally I think Incoboto had good intutitive touch controls. Left side of the screen to go left, right side to go right, swipe either side to jump in that direction. Maybe not suited for something fast paced like League of Evil, but felt natural and worked for that game. And regarding your first question, I always prefer touch controls to be the default movement of left, action on right,
I really like the platforming controls using swipes used in Limbo, Prince of Persia Shadow and the Flame, mirror's Edge, Project 83113, and He-Man. What i like about these swipes is that you arent forced to use peripheral vision to make sure you touch the right buttons. On the other hand, games like League of Evil series, the Orangepixel platformers, Mikey series, Ark of Sinners and Swordigo among other great platforming titles on iOS already proved that virtual buttons can work perfectly when done right.
Hmm, are there any moments where you'd have prefer virtual buttons? I feel that there is some loss in precision since most moves activate at the end of the gestures instead of the beginning of a touch. Also some people like controlling their jumps arcs and manipulation their movements while in the air. That's really hard to do with swipe controls. For a slow-paced game, I guess those issues don't really matter?
I'm a huge fan of on screen buttons for platformers and not swipes Look at some of the most popular ios platformers such as the League of Evil series or OrangePixels platformers. Look at Muffin Knight etc. All use on screen buttons and do it very well
For the games which swipe controls work well, they usually have a fixed arc for the jumps and cancellable animations for the rolls, slides or crouches. For a more precise platforming like having mid-air maneuvers, on-screen buttons have proven to be the better option.