An Epistemological Problem for Idealists

I think this is a defensible inductive argument by analogy for the idealist who wants to propose the existence of a god or super-mind:

(1) the idealist:
We observe things directly that claim to be minds that probably have minds (e.g., people). On analogy, there might be an unobserved super-mind or super-minds that are the external cause of our perceptions of these things.

First, the inference that there may be a super-mind that is the external cause of our perceptions is a hypothesis, a thing proposed on inductive analogy.

The idealist has no direct or immediate access to the super-mind, and actually it does not even follow from his argument that there need be a single mind at all.

Actually, from the inductive analogy as above it is logically possible that the postulated cause could be:

(1) a single super-mind

(2) two single super-minds

(3) three super-minds

(4) four or more super-minds, etc.

Furthermore, once we get to very large numbers of postulated super-minds, suddenly a panpsychical idealist may propose the following analogy:

(1) the panpsychical idealist:
We observe things directly that claim to be minds that probably have minds (e.g., people) and animals that appear to have less sophisticated minds (e.g., without language). On analogy, it might be that all objects of perception are external independent minds of different types and the cause of our perceptions of these things.

Some philosophers have seriously proposed this view, and idealist panpsychism is a real view.

A variant on panpsychism is personal or pluralistic idealism which proposed many independent minds that somehow collectively generate an external mental realm with consistent ideas, but with no absolute mind (e.g., the idealism of John M. E. McTaggart, who denied that any god or absolute mind existed).

So now we must add to our list of logically possible hypotheses about minds that might be external causes of our perceptions:

(1) a single super-mind;

(2) two single super-minds;

(3) three super-minds;

(4) four or more super-minds;

(5) no super-mind or super-minds but vast numbers of external independent minds corresponding to each object of perception;

(6) there are many independent minds that collectively generate an external mental realm with consistent objects of perception, but with no absolute mind.

So what arguments can the idealist employ for defending (1) to argue it is more probable than (2), (3), (4), (5), or (6)?

I contend the preference for (1) is mainly a legacy of Western monotheism.

Why? The reason is that, when we propose or think of some greater being that is the causal origin of us, the natural way to think in our culture is a single Judeo-Christian god or some single being like it.

But that tendency to make people accept hypothesis (1) is a mere bias. For example, someone from a polytheist society might lean towards (4) when considering idealist arguments.

So what rational arguments can the idealist offer to defend (1)?