Used statspack to analyze performance:
Here is one section:

Instance Efficiency Percentages (Target 100%)
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Buffer Nowait %: 100.00 Redo NoWait : 100.00
Buffer Hit %: 99.66 In-memory Sort %: 99.92
Library Hit %: 99.93 Soft Parse %: 99.89
Execute to Parse %: 0.62 Latch Hit %: 100.00
Parse CPU to Parse Elapsd %: 91.65 % Non-Parse CPU: 97.10

Everything looks OK except the extremely low Execute to parse ratio.
I was using CURSOR_SHARING = SIMILAR.

Any suggestions as to how to force Oracle to execute more for every parse. My application is a complex telecom facility design solution.

Thanks,

Nizar