Indeed the term "eternal" is something I do not use in reference to God because the term basically means time without end. Instead I use the term "timeless" because time is part of the Creation and not a property of or restriction on the Creator of it.
I am simply using established theological trinitarian terminology, in other words what some other self-professed genius established as norm.
The word eternal is derived from Latin æternum, which is derived from Greek aiones (ages, æons). There is no element of time in any of them. It hepls to know the meaning of the words before micharacterizing and discarding them.
Let me know when the theological world accepts your "timelessness" as norm. Maybe then it will be relevant.