Don't know where you heard this. It's not true. The "likelyhood [sic] to hit" is about your coordination, not what's going on at the end of your wrist.
"are used for an easy transition to wrestling if need be"
Again, not sure where you heard this. Any impact will drive the opponent away; if you want to wrestle, you need the guy in close. That's just physics.
You can totally uppercut with a palm. You just have the palm facing away instead of facing towards you.
You can also palm-strike on pretty much any angle you can punch along. Again, what's going on below your wrist is the least important part of the equation when it comes to aiming and trajectory.
As for being "more powerful", I don't know. Perhaps marginally. I've heard, though I don't know if there are any studies to back it up, that hitting with the front of a fist will compress the bones and tissue in the hand, and some of the energy from the punch is lost when that happens, compared to hitting with a palm. It makes intuitive sense, but again, I don't know if there's any actual science behind it. We do know for a fact, however, that punches still knock people out.
How will being tall effect the trajectory of your strike? It really shouldn't. You shouldn't strike below the level of your shoulder. If your target is below your shoulder level, widen your stance and bend you knees until it isn't.
Some "experts" recommend striking with the palm because it's easier to break the knuckles of a fist than it is to hurt yourself while delivering a palm strike. My own coach/instructor pointed to something called the "Moro reflex", which is when primates grab (make fists) in response to stress, as a reason to stick with punches, however. And hitting with the palm doesn't mean you'll never injure your hand: Bas Rutten broke his hand while striking with the palm in one of his Pancrase matches, which forbid close-fist strikes to the head. I would say it's safer, relatively speaking, to punching, but unless you spend a LOT of time training palm strikes on the bag, on the pads, and in sparring, you're probably not going to be any more proficient with using them against another person.
Not to sound disrespectful, but based on several things you've written here, I'd suggest that you have yet to build good striking fundamentals. Work on that before you worry about whether to hit someone with a palm or a fist.
They are both effective, neither is better. whichever one you practice with more will be more effective, but you should practice punching and palm strikes, there's good times for each. You can even use punches as a fake jab and a palm strike at the end of the combo if you wanted.
Your hand is not designed by nature to punch people which means using fist you'll have higher likelihood to hurt yourself if you punch the wrong place (unless you often train in punching hard object). Using palm is a better and safer way in engaging a fight.
Different strikes are for different situations. Fights are, by nature, unpredictable. Thus, it is preferable to be proficient in a variety of defensive and offensive techniques.
You have to practice.
I'm still thinking about it. Palm strikes are safer, have more of a likelyhood to hit, and are used for an easy transition to wrestling if need be. But punches are better because there are more angles, right? You can't really uppercut or shoot for the body with palm strikes. And punches hurt more, right?
I'm confused. A lot of experts say that palm strikes are definitely better. And I'm tall, so wouldn't palm striking someone put my arm at a weird and less devastating angle?
Is it true that palm strikes are more powerful than punches?
