Background
From Ladybug's answer to this other question, I learned that, where an Indikativ Präteritum mental-state (e.g. "fühlte" or "dachte") introduces a Konjunctiv II Plusquamperfekt irreal (counterfactual) situation, the situation can be either coeval with that Indikativ Präteritum or more remote in the past.
I'm sorry that was complex; but I hope the following examples (simplified from Ladybug's answer) should make the meaning clear, where {-1} refers to a past time and {-2} to one even more remotely in the past.
(D1') Ich fühlte{-1}, welchen Spaß es mir gemacht hätte{-1 or -2}, spazierenzugehen, wenn da nicht Mama gewesen wäre{-1 or -2}.
(E1') Ich fühlte{-1}, wie gerne ich spazierengegangen wäre{-1 or -2}, wenn es hier nicht die Geschichte mit Mama gegeben hätte{-1 or -2}.
Put another way, these sentences can mean either that "ich" at a past time regretted (i.e. {-1}) not being able to take a walk right then and there ({-1}) or not having taken a walk earlier ({-2}).
Question
My question for this post is this: To express a subject's past mental-state about a coeval counterfactual, can you use an Indikativ Präteritum mental-state introducing a Konjunctiv II Präteritum counterfactual?
By way of example, we may ask:
Examples 1. Can the following sentences be used to state that, at some pont in the past, "ich" wished for a walk right then and there?
(DD') Ich fühlte{-1}, welchen Spaß es mir machen würde{-1}, spazierenzugehen, wenn da nicht Mama wäre{-1}.
(EE') Ich fühlte{-1}, wie gerne ich spazierenginge{-1}, wenn es hier nicht die Geschichte mit Mama gäbe{-1}.
(I note that "machen würde" is in KII Future.)
Example 2. Can the following be used to state that "ich" considered what would be better right then?
Ich dachte{-1}, es wäre{-1} besser.
Example 3. Can the following be used to state that Meursault thought that he would be better off without his mother?
Eines Morgens dachte{-1} Meursault daran, wie viel besser es wäre{-1}, ohne seine Mutter zu sein{-1}.
If the answer is yes, then we will end up with two ways to express a past mental-state about a coeval counterfactual: an Indikativ Präteritum mental-state introducing either (1) a Konjunctiv II Plusquamperfekt counterfactual (from Ladybug in the other post) or (2) a Konjunctiv II Präteritum counterfactual ("yes" to this post).
Comparison to Other Languages
Incidentally, what is analogous to (2) in French, i.e. an imparfait mental-state introducing an imparfait/présent conditionnel counterfactual, is apparently ungrammatical. I.e. French can only do (1). See comments to Kyrio's answer in this post in the French section.
In English, I believe, what is analogous to (2) is allowed and even to be preferred to (1). See the English portion of Examples 2 and 3, in which a past tense mental-state introduces a "would" counterfactual. (I expect you felt no resistance reading them.)
It'd be great if anyone took a look at my "hypothetical" answer to the other question, which is somewhat related to this one. Thanks.