That is a nice creed and you have made an excellent point. We have the Nicene, the Apostle’s and this and I don’t think we need to make a new one. In fact, I’d be a bit worried about anything new we would come up with.
“If it ain’t broke, don’t fix it.”
Problem is ... to look at some of the FR religion threads (and some of the real-world fights as well), it's quite clear that the Creeds have ceased to inform many about our common Christian beliefs.
IMO, the worst offenders seem to be the Catholic bashers, followed closely by the Mormon-bashers (I choose not to get involved in that particular debate....)