If I have top entrances I don't need mouse guards. I don't like bottom entrances for several reasons. When my parents kept bees my father used to get stung at his feet and lower legs because they are right by the door. Dad used to have mom customize his bee suit to cinch down a the ankles. I have never been stung below my waist. The day my dad said he got stung the worst was when they had propolized the boxes together and he thought he had them broken apart and he lifted and they were still stuck and he dropped the bottom box. That didn't make the bees happy. With top entrances I may still have the boxes stick together but they won't be rushing to sting my feet. The rodents and skunks are not as big a problem either. When we have a spell of drastically cold weather I do plan to put something by the hives as a heater.
put the hives on a stand...
stand ,bottom entrance, no top vent, insulation they are all part of the system.
Stands keep the critters out and the snow out
bottom entrance and no top vent keep the hot air in.
insulation puts the condensation to the side and below and makes both the bees and the condensation warm
let me guess you dont want to put the hives on a stand