Lots of information for you to digest. Brief synopsis of what I have seen looking at the information. Cow tag will take at least 1 preference point to draw. Buck tag is also valid in unit 41 and 421, the hunt code is DM041xxR. xx = the season you choose. Looks like you will need a preference point there as well. Keep in mind that I looked at this info very briefly and the preference point info may not be correct. All my information is based on the assumption you are hunting with a rifle. The info for archery and muzzleloader is in the stats as well.
I can't give you an answer for that one. Depends on which part of the unit you are planning on hunting. Some parts are probably better in the second season and some areas would be better during the third season. Maybe someone else on the site could give you some pointers without giving out their secrets.. You could also try to call the DOW officer in the area.
If you're lucky enough to be on private land and can leave your stand up during the off season you can tie an old piece of cloth or something of the sort to your stand. I like to use an old camo bandana that I have. That way the deer get used to the movement and eventually don't bother even looking up when there is slight movement. This may just give you the time to draw your bow or raise your gun without being detected.