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Oxygen is a highly reactive element, regardless of any of the points you've mentioned. Unless it's being replenished, it cannot remain free as a gas in any atmosphere. As a matter of fact, all of those processes would be conducive to oxygen being taken up just as rapidly as it would be on Earth, without the presence of life.
Most abiotic processes which liberate Oxygen from minerals are highly endothermic and require quite a bit of energy input to begin with. Any planet which exhibited such characteristics would most certainly not be habitable unless it was by silicon based organisms. To release enough Oxygen into an atmosphere via these processes (to sustain it at high levels) would melt the surface of the planet. Actually, it would most likely melt the planet right through. The normal range of processes are inadequate when it comes to producing and sustaining Oxygen in substantial quantities in planetary atmospheres.
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