  For quark matter studies in astrophysics the thermodynamic bag model (tdBAG)
has been widely used. Despite its success it fails to account for various
phenomena expected from Quantum-Chromo-Dynamics (QCD). We suggest a
straightforward extension of tdBAG in order to take the dynamical breaking of
chiral symmetry and the influence of vector interactions explicitly into
account. As for tdBAG the model mimics confinement in a phenomenological
approach. It is based on an analysis of the Nambu--Jona-Lasinio (NJL) model at
finite density. Furthermore, we demonstrate how NJL and bag models in this
regime follow from the more general and QCD based framework of Dyson-Schwinger
(DS) equations in medium by assuming a simple gluon contact interaction. Based
on our simple and novel model, we construct quark hadron hybrid equations of
state (EoS) and study systematically chiral and deconfinement phase
transitions, the appearance of $s$-quarks and the role of vector interaction.
We further study these aspects for matter in beta-equilibrium at zero
temperature, with particular focus on the current ~2 solar masses maximum mass
constraint for neutron stars. Our approach indicates that the currently only
theoretical evidence for the hypothesis of stable strange matter is an artifact
of tdBAG and results from neglecting the dynamical breaking of chiral symmetry.
