You have trouble with touch interface in sunny conditions??? Try cold conditions with gloves on, then you'll have real problems with the Apple Watch. Or wet conditions. Or fast conditions like on a bike where you rather not look to turn off the alarm. Sunny conditions is the only time my watch works fine.
Wet is always a disaster, though. If it's going to be moist outside (like hiking with a rain jacket), you have to remember to apply water lock immediately, or you're done for. In that case, the watch is pretty much useless until you get back inside, which is in fact very annoying.
