Trying to answer a few of the questions above ...
Dryer - really isn't very practical here in S.Texas, humid air will require you change the dryer media every few days. The ozonator will be more efficient with dryer air, but the general approach is to buy a higher output unit than needed, no dryer, and let it run longer to reach the ORP target.

I just soak my probe in Vinegar (hot vinegar) for a minute or so. Leaving a second one soaking a long time wouldn't be a good idea IMO. Doesn't take long to clean, and a 2nd one will cost a good bit of $$s.

If you smell ozone it is either 1) escaping from the skimmer, or 2) getting into the sump water and escaping from there
1) is bad for your health & will oxidize stuff in the room quickly - add some dry carbon where air is exiting the skimmer cup
2) Can have serious health impact on your fish & corals - run carbon in the skimmer drain to the sump.

I have dry carbon on top of my skimmer cup, no carbon in the sump because I have a VERY long linear travel of water (slow moving) before it reaches the return pump.

Hope some of this helps?