I've read various ideas about pre flop raising and they seem somewhat inconsistent so I wonder what people's experience has taught them?

Principle 1 - don't build a big pot OOP. This would suggest smaller pf raises in EP and larger ones in LP

Principle 2 - Make larger raises in EP to discourage callers as all hands are harder to play OOP. Re-raise more aggresively OOP to try to end the hand immediately. This suggests the opposite...

Principle 3 - always make the same size raise so you can't be read

Principle 4 - size your raises according to the situation - value, isolation, deception etc mixing it up sometimes to confuse anyone watching.

Currently I follow principles 1 and 4, just wondered what people think. I only play 10NL by the way.