Does it matter if the power in goes into fixture before switch?
What you are proposing is called a switched neutral and is not a good idea, as well as being against code. The problem is that if you turn off the switch, there is still power being applied to the light fixture. If you go to, for example, replace a broken light bulb (where the base was left in the socket), even with the switch off, you could be electrocuted!

You should add the wire loop so that you can switch the hot side.