This paper is a continuation of ArXiv:0707.1324 where improved holographictheories for QCD were set up and explored. Here, the IR confining geometriesare classified and analyzed. They all end in a "good" (repulsive) singularityin the IR. The glueball spectra are gaped and discrete, and they favorablycompare to the lattice data. Quite generally, confinement and discrete spectraimply each other. Asymptotically linear glueball masses can also be achieved.Asymptotic mass ratios of various glueballs with different spin also turn outto be universal. Mesons dynamics is implemented via space filling D4-anti-D4brane pairs. The associated tachyon dynamics is analyzed and chiral symmetrybreaking is shown. The dynamics of the RR axion is analyzed, and thenon-perturbative running of the QCD theta-angle is obtained. It is shown toalways vanish in the IR.
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