Topband: Beverage Question

[Charlie Young]

Starting my 3rd season on Topband.  I have some beverages installed, but due to my terrain and the layout of the property, they are far from optimal.  The longest one is only 450' long and the others are 300 to 350'.  One of them runs upslope, a couple run downslope and a couple run sort of sideslope.  They all seem to work after a fashion.  I suspect they would work better on 160 if the length could be increased. 
 
My beverages are all constructed out of aluminum electric fence wire, which is cheap and has held up well.  My question:  Would it be beneficial to replace the bare wire with insulated wire to make the beverages appear electrically longer? 
 
I have the option to put up a longer NE wire, but it will run steeply upslope for the first 1/2 of the length, then steeply downslope for the remainder and we might do 600' to 700' with this one.  If I build it, we could use insulated wire.  I would consider changing the others to insulated wire if it would make a real world difference.  
 
Thanks for any responses.
 
CU on Topband
 
73 Charlie N8RR