[PxTx]

Well, the return line comment is more for when you go electric. The fuel staving problem is probably your effort to prevent those green fragments from getting into your fuel pump.

I would not have any filter between the fuel tank and your pump- be it electric or mechanical. A pump typically does much better at pushing. A filter before it is a restriction. Your air bubble in the filter before the pump is trapped air. The filter will not fill up until tha air can purge out. That air bubble is also a restriction.

When the time comes for the electric fuel pump, I would encourage you to run a lare, 1/2" aluminum line as the main feed. You can use the old 3/8th as the return line from a nice regulator. The important part is that the new line has a good pickup so it doesn't suck air. The pump is designed to push, and will have a flame arrestor screen that will be adequte to keep any debris large enought odamadge the pump out. Put a filter on the push side of the pump to protect your carb. I know there are two schools of thought on where to place the filter, but I beleive they do more harm that good when placed before a pump.