I think the stylus-driven controls work really well. The game is extremely responsive so the movements are fluid. Unless you poke the screen SUPER HARD, the game shouldn't give you hand or thumb pains(imo), at least not for +4 hours but who plays a handheld game for 4 hours straight!
you have to quickly draw little lines or circles between link's and the enemy's sprites to do an attack (or draw a big circle around link to do a spinning attack). Only it gets pretty hard to position yourself properly to do an attack since you also need the stylus to move around and also because usually there are multiple enemies moving around you all the time. I had trouble with the fucking slimes in the beginning of the game so that says a lot about the controls.
I disagree with this. Attacking is really easy. You can choose to target the monster directly so I don't get how you had trouble with the slimes in the beginning...especially when they move extremely slow. Then when there are times where you would usually miss because the monsters are moving faster than your "targeting," I don't find it hard to draw a line to attack that monster either.
One of the major problems I had with the controls was rolling towards bottom right or bottom left because the Menu and Item commands were in the way so you HAD to walk for a bit(to wait for the commands to disappear), then you could roll. But I find rolling useless in the game anyway.
I agree with konix on the topic of the ship. Drawing a line to guide the ship means sitting there for 5 mins, shooting monsters randomly(which, is not fun by the way because you can target the monsters so it's more annoying than fun).
Using the D-pad or buttons as shortcuts is a nice feature. I find myself using these shortcuts often because it's faster than selecting the icons to the 3 corners if you can press the buttons with your free hand at that moment.
So yeah, I think the game is fine.