Do you honestly think you've come up with a clever idea that none of the researchers in the field already considered?

You are describing MACHOS, which was one hypothesis for dark matter. https://en.wikipedia.org/wiki/Massive_compact_halo_object

The thing is, we've looked for them. If they were small (asteroid sized), the amount required would be visible as dark clouds obscuring the objects behind them. If they were large (brown dwarf or bigger), we'd see gravitational lensing from them. We don't really see either of those on the scale required to explain the gravitational effect.