Yes, the great thing about these trusts, is not being subject to the millions of ever-changing statutes, but rather only to the everlasting and ever-the-same natural law, you basically have limitless freedom and flexibility to design, adapt, modify, and operate the trust any way you like, as long as you don’t use it to violate the rights of anyone else, or the basic rules of good trust construction.
A spouse can be one of the trustees, but not First Trustee or Protector. And a couple cannot be co-trustees. A spouse can be one of the trustees as long as the other trustee is not a family relation of any kind. You and a relative who is not a part of your household can be co-trustees, as long as that relative is no closer than a first cousin. No lineal antecedents or descendants.
Not every trust has a protector – they are not always deemed necessary. A protector has the power to hire and fire trustees. It depends upon the objectives of each trust creator and the relationships he or she has available. But if one is appointed, the protector must not be related to the settlor or any of the trustees or beneficiaries.
Assuming these conditions are fulfilled, you can make the powers, responsibilities, and privileges of each of you as specific or as general as you wish. You can also make her manager, successor trustee, or beneficiary. Or, if you really want to give her complete freedom, you can set up an entirely separate trust for her and encourage her to be manager or trustee of it. There are lots of ways you can go. Further details on the “how” of it, specific to your situation, are better discussed with the trust writer.