Without to much of a technical knowledge in the area (plenty of interest just not to the paper reading level) I have been sceptical of dark matter as an undetectable equation balancer. Any good research into dark matter that I should read that puts forward a better case than balancing equations?
Another problem we have, is that we have one point of observation into the unimaginably big universe. Given our limited view overfitting the data to support some model is likely.
The present theory concerns the elimination of dark energy, not dark matter. The existence of dark matter has been demonstrated beyond any doubt through observations of a collision between two galaxy clusters. In a nutshell, the clusters were mostly made up of high-energy plasma, and when they collided almost all of the plasma remained at the point of collision due to electromagnetic interactions between the gases. However, the dark matter in the clusters, which was previously difficult to observe independently, passed through the point of the collision (that is, through each other) as though nothing had happened. The electromagnetic interactions trapped the visible baryonic matter in one spot while the dark matter drifted off into space, allowing us to observe it independently via the effects of gravitational lensing.
Another problem we have, is that we have one point of observation into the unimaginably big universe. Given our limited view overfitting the data to support some model is likely.