Your method seems to be okay if you feel it is what works best for your family. The chosen method doesn't have to be too rigid (like strict OPOL). You can use a variation as you think it suits you.
It looks like you are using a combination of minority language at home (when your husband is present because you are fluent in his language and are used to speaking to him in his language), and OPOL when he is not around, when you are with friends and family.
In our case, I speak the minority language and my husband is native speaker of the majority language but like you he is fluent in mine. We chose the "minority language at home" method, as we thought our son would learn English first at the nursery and later at school. We wanted to give the best chance and exposure we could to the minority language by doing this.
My husband speaks to our children using the minority language always, whether I am with them or not. The exception being when we are out with friends or with his family. Then he speaks to them in English (the majority language).
I, on the other hand, always use the minority language no matter what, even in the presence of friends and family, unless I am addressing other children or people present.
Most of the friends that speak my language are usually married to someone who is not fluent in the minority language and use OPOL; but more often than not, these children end up being passive bilinguals (they understand the minority language but reply in the majority).
Once your daughter starts talking you'll be able to see if she is equally proficient in both languages or if one is stronger than the other. Depending on the situation -since you are fluent in both- you should be able to increase exposure of one or the other as necessary.
It is okay to speak both languages to your child, as long as there is consistency with the method used and enough exposure to both.
Good luck!