A few thoughts, mostly similar to ones I left in a comment a few days ago. First, it may be true that "unlimited agent" may be a simpler concept than any specific limited agent, but FWIW it should be noted that "agent" is already smuggling in a decent amount of complexity, at least if it's referring to a mind that has desires, plans and decisions.
Second, it's not clear why (say) moral perfection is something an unlimited agent would have, if we're being moral realists and building that into our concept of God. Why is moral perfection less limited than complete moral indifference, or being perfectly evil? In fact, it's not really clear that the concept "limit" as you're wielding it is really all that simple, itself; maybe, like "perfection," it's (IMO) implicitly tying together a bunch of unrelated things, or maybe it actually depends on the notion of minimal description length in some way.
Third, "limitless agency" or "limitless knowledge" or "limitless power" or any of those things might be simple, but under-specific. For example, if there's more than one way to have limitless power or the like (e.g., deities that can preserve anything versus deities that can destroy anything), then "limitless power" doesn't completely characterize God or God's powers, and so that description fails to capture God's full complexity, much like the relatively simple description "is based on manifolds" fails to capture the complexity of general relativity.
A few thoughts, mostly similar to ones I left in a comment a few days ago. First, it may be true that "unlimited agent" may be a simpler concept than any specific limited agent, but FWIW it should be noted that "agent" is already smuggling in a decent amount of complexity, at least if it's referring to a mind that has desires, plans and decisions.
Second, it's not clear why (say) moral perfection is something an unlimited agent would have, if we're being moral realists and building that into our concept of God. Why is moral perfection less limited than complete moral indifference, or being perfectly evil? In fact, it's not really clear that the concept "limit" as you're wielding it is really all that simple, itself; maybe, like "perfection," it's (IMO) implicitly tying together a bunch of unrelated things, or maybe it actually depends on the notion of minimal description length in some way.
Third, "limitless agency" or "limitless knowledge" or "limitless power" or any of those things might be simple, but under-specific. For example, if there's more than one way to have limitless power or the like (e.g., deities that can preserve anything versus deities that can destroy anything), then "limitless power" doesn't completely characterize God or God's powers, and so that description fails to capture God's full complexity, much like the relatively simple description "is based on manifolds" fails to capture the complexity of general relativity.