Arrows have a bigger range and are much cheaper.
Doesn't matter, it's still cheaper than enderpearls.
If by easily countered you mean a shield, do the math. Other than that there's no sound way to move around islands without getting shot at.
Also "it can break" yeah like this ever happens.
It gives you tremendous stopping power. No matter what arguments you come up with,
Price of punch bow: 25 diamonds
Use: infinite.
Price of enderpearl: 64 diamonds
Use: once.
still applies. You can get a punch bow a lot sooner than an enderpearl. A punch bow is permanent, an enderpearl one-time use. Miss your enderpearl or land too close to the edge, you're dead. Miss a bow shot, no big deal.
Defense shouldn't be better than offense, if you want that to be the case, look for a different game than eggwars.
I mean, the game is all about the defense of your egg...
I've had bows break on me before. It happens fairly often. Especially when you're breaking an opponents shield with it.
An enderpearl is a great risk for a great reward. If you aren't prepared enough when you throw it, the outcome could be worse than you expected. Makes sense.
Anyways, if the opponent is camping, and it's just you vs. them, how is cost a barrier? If you have mid, and all the other islands, and they have no egg and just one, how is 64 diamonds prohibitive? Dying isn't even a problem because you can just get more stuff and try again. Campers can't stop you if you try hard enough. I don't even know why I'm still arguing this. I haven't met a real camper in months, and they aren't that hard to deal with.