I somehow used LOL=140 for my calculations. You specified 130.
UL to OL = -84dBm (Value seems fine)
But as you said, by increasing it your drop rate increased. It is due to handing over call to OL even at lower UL levels.
You should try to uptilt the OL by 1 degree. (in case you are not using Own BCCH in your MF list). This will make OL levels better slightly and OL will retain call longer. (However if you see increased drop rates due to call dragging, you will have to revert the settings. This is very much dependent on terrain profile)