All of this is valid. However, and here the OP is right: A small vessel ramming a much bigger vessel with a superior shield should not have a chance of popping it. And this is exactly what happens. THIS is a game flaw.
I got rammed by a completely shielded up Anaconda in boost speed and I was in an Asp Explorer. My shields went down and I lost 75% hull, but I survived.
That the OP could be taken out by a ramming Sidewinder or whatnot is troubling. There needs to be some logic behind the ramming mechanics.
It depends on where you get hit. Any spaceship flying straight into your cockpit will cause major trouble. Remember even a sidewinder weights a couple dozen tons and the collision speeds is usually a couple hundred meters per second. That is a lot of energy aimed at a fragile part of the ship.