I’ve tried quite a few different brakes, and have original Hope Minis which I prefer to my Hayes 9s, for feel*. But the truth is that all the ones I’ve tried have had more or less the same amount of ‘power’. If you want more stopping power, consider larger disc rotors, say 180mm rather than 160mm.
*Hope are more positive at the lever, feel nicer when feathering the brakes. The Hayes feel more vague and not quite so solid. The Hopes are better quality. The Hayes have needed a lot more fettling to keep them running well, whereas the Hopes have been ‘fit and forget’, pretty much.
Of course, pad choice can change how the brakes feel; some pads wear faster but offer better braking, some are more durable but don’t feel quite as good.
Oh, and proper clean pads can make a noticeable difference too. I clean mine by ‘sanding’ the pad surface down using a bit of mud. Brings them back good as new. 🙂