That's actually what I was originally going to do (incorporate a screen into a hellman style tank sump). I didn't have enough time to get the sump made so I'm just using a bulkhead fitting and external filter for now.
If the screen in the sump got plugged it would suck, but I really don't see how that would be any different than any of the stock style applications that all use some sort of filter sock or screen inside the tank to filter the fuel before it goes into the pump. If it were up to me on how to design it I would be trying to come up with a flanged type of screen that would sit on top of the flange inside the fuel tank. That way the screen would stay clear as the fuel sloshes around on it.
If the screen in the sump got plugged it would suck, but I really don't see how that would be any different than any of the stock style applications that all use some sort of filter sock or screen inside the tank to filter the fuel before it goes into the pump. If it were up to me on how to design it I would be trying to come up with a flanged type of screen that would sit on top of the flange inside the fuel tank. That way the screen would stay clear as the fuel sloshes around on it.