The first five problems on our list are the most generic and intractable in DM models. Problems 1, 2 & 4 do not merely arise from mismatches between theory and observation, but require fine tuning in any DM scenario. Any physical process to account for them must somehow couple the dark and luminous components. If the only interaction between the baryons and DM is gravitational, it is hard to imagine how such a mechanism could arise.
Problems 7-10 are well-rehearsed difficulties of CDM. The possibility that 7 & 8 could be solved by a more realistic treatment of baryonic processes alone is remote since they relate to the total mass distribution which, in the simulations, is dominated by DM. Even if the baryonic mass fraction is significant, it is unclear what process could loosen tight DM concentrations; for example, Debattista & Sellwood (2000) show that an intolerable degree of dynamical friction has a very mild effect on the halo density profile. Problems 9 & 10 could conceivably be solved by some kind of complex baryonic physics (i.e. star formation), but this solution to 10 would require more fine tuning.
Another approach to problems 7-10 is to modify the assumed properties of the DM particles. Warm DM (e.g. Colombi, Dodelson & Widrow 1996; Sommer-Larsen & Dolgov 1999; Hogan 1999) is designed to aid problems 7 & 9 in two ways: WDM particles stream freely in the early universe suppressing small-scale power. They also have larger velocity spreads in halos of greater volume density, because of Liouville's theorem, thereby precluding strong density gradients. However, fermionic WDM falls foul of problem 6, while bosonic warm DM, which has a small fraction of very high phase space density material (e.g. Madsen 2000), would probably again form cusped halos as in CDM. Self-interacting dark matter (Spergel & Steinhardt 1999) can in principle solve problems 7 & 9 (Burkert 2000; Davé et al. 2000) but only if the cross section is tuned; it may also have difficulties with its prediction of spherical halos. We emphasize that hypothetical modifications to the properties of DM particles have been motivated mostly by problems 7 & 9, and any collisional effect removes 6, but none address the much more difficult problems 1-5.