From what the Venerable Ledi Sayaadaw says, it seems that Okappana saddhaa
is more stable and stronger than pasaadha saddhaa. I would equate it to
the confidence born of conviction, having made a thorough study of Dhamma
or having practised meditation. While pasaadha saddhaa would be the
confidence born of tradition. Pasadeyyaasi literally means `to make one
cheerful.'

I wonder whether it is not better to avoid the word "faith" altogether,
and to use "confidence"

(1) confidence through attainment (aagamana,saddhaa),

(2) confidence through realization (adhigama,saddhaa),

(3) confidence by conviction (okappana,saddhaa),

(4) serene confidence (pasaada,saddhaa),