If I missed this, I apologize, but how deep are you wanting to fish? For instance I wet wade local rivers in the summer and use nothing but a floating line. Clousers are weighted and get down to the bottom for me. When streamer fishing I normally present them somewhere from just under the surface to close to the bottom. If I want to go deeper I'll just throw a mend up stream. When I feel I need to go deeper I will use a sink tip. If I was fishing lakes and or ponds more I would consider a density compensated full sinking line.

As far as a sinking line for a 4wt is concerned, I only use sinking or sink tip lines on heavier rods such as a 6wt on up. Unless you are throwing very small Clousers I would think you might have some problems throwing them on a 4wt.

Dave