I believe God is one, in whom is the Divine Trinity, and He is the Lord God the Savior Jesus Christ.
IF this is what you believe, why do you say the Holy Spirit is a separate entity?
This is a bit different formulation, but I don't see how it removes your objections, one/trinity - three/one wise.
With a little change, it's pretty close to Orthodox Christian belief:
"I believe the Godhead is one, in whom is the Divine Trinity, comprised of God the Father, the Lord God the Savior Jesus Christ and the Holy Spirit.