You won't have inverter/freezer running all the time. Those freezers that I know, are cycling. So there is no guarantee that there won't be some periods when the battery has no loads and the cold weather mandates Absorption ~15V. To be on the safe side, I would try keeping the voltage drop so as to provide the controller input not lower than 15 at 77F. It can be higher than 15, - the controller will limit the upside as you said - but it shouldn't be lower than 15.
AC freezer does render the whole debate kind of moot. With a load like this, plus your other loads, a 140W panel is very, very little, in terms of daily amp-hours. You will still have to run a genny some hours every day. And, with almost permanent high current of the freezer - off cycles won't be long enough - you won't benefit from finishing the charging silently with a low current of the panel.