If I could change conventions

In order to represent concepts in math and science, we use definitions and conventions that just "are". Nobody questions them because it's all we have come up with. But there are a couple of things that I was taught where I said "wait a minute, this is not a good convention!"

Take for example pi, aka 3.14159. It is the ratio of the circumference of a circle vs. the diameter. And we give it the unit of radians. But it takes 2pi radians to make one circle. Why didn't they make pi = 6.28?? That way, one pi would represent one circle (or pie if you will). So pi should really be 2pi. Wouldn't that make a lot more sense?

My other pet peeve is the fact that it was arbitrarily decided that protons would be "positive" and electrons would be "negative". This has caused all sorts of confusion, particularly when we talk about electrical current flow. Electrical current is the flow of electrons from one point to another, more specifically from a negative point to a positive point. So you would assume that the electrical conventions would be set up to support this. But everything is the opposite! Conventional current flow is positive to negative. So what exactly is flowing positive to negative? It's not electrons, but rather the absence of them! Now, if we said that electrons had a positive charge then everything would make sense. Electrons would flow from positive to negative (as we would expect) and a collection of electrons would mean a greater positive charge which would in turn produce a greater positive voltage. Electronics would make a lot more sense and this engineer would be happy.