Writers Block

As a songwriter, ideas seem to come in waves for me, some are complete thougths, some snap shots, it seems that the snap shots end up in a multi volume notebooks full of cool phrases and incomplete stanza's. After the waves stop, I ultimately go back to these phrases and try to finish or complete the idea. In the past, the ones that I have finished end up being subpar material full of cute wording that lacks substance and heads to the chopping block. A very small few end up making the cut and turning into something worth sharing. I'm getting to the point where I would just assume leave them alone if they didn't come to me in completion, but I worry that there's an idea or phrase that could turn into something much bigger than me. What would you do with these ideas if you were in my shoes, or maybe you wear a pair similar to mine and have the same problem.