In modeling, when you specify a trade's Starting Price, this is currently the full debit or credit in whole dollars for the entire trade (regardless of how many contracts are specified per leg).

In order to remain consistent with typical options chains, could this be changed to accept dollars and cents ? For example, if I sell 2 puts at $0.75 credit, I should be able to use Qty 2 and credit of $0.75. OO will then know this is a total credit collected of $150.

For ratio spreads, take the base ratio or the smallest irreducible ratio (e.g. -3/+5 is priced in it's entirety, whereas a -3/+6 ratio would be priced as a -1/+2 with 3 lots, or a +2/-6/+4 unbalanced fly would be a +1/-3/+2 with 2 lots). This is consistent with how most trading platforms handle ratio spread pricing.