Combining different verb forms

[dairwolf]

I was wondering whether it makes sense to change the original verb in patterns like 食べなくなる, 食べてしまう, or 読も終る so that they become e.g. 食べさせなくなる (causative - I won´t let them eat anymore), 食べられてしまう (potential - I could eat it completely) and 読め終る (I can read it until the end).

And does it make sense on the other hand to change the auxiliary verb itself? For example:
なれる (potential) - it/ I can become
分かれる (potential) - I can understand it.
分からせる - (causative) - I´ll let someone understand.
知られる (passive) - it is being known
あげられる (potential) - I can give it.
もらえる (potential) I can receive it.

 

[Toritoribe]

I was wondering whether it makes sense to change the original verb in patterns like 食べなくなる, 食べてしまう, or 読も終る so that they become e.g. 食べさせなくなる (causative - I won´t let them eat anymore), 食べられてしまう (potential - I could eat it completely) and 読め終る (I can read it until the end).

There's no form such like 読も終る and 読め終る.
食べさせなくなる means 食べさせないようになる or "to become to make someone not to eat." What you wanted to say might be 食べさせなくする.
"I won´t let someone eat anymore" would be more likely 何も食べさせない. Similary, 食べられてしまう is "The subject is eaten."
The potencial forms "I can eat it completely" and "I can read it until the end" should be 食べてしまえる and 読み終われる, respectively.

分かれる (potential) - I can understand it.

わかれる[別れる/分かれる] means "to separate." It's never used as a potential form, since the verb わかる itself has a sence of "to be able to understand." You can use 理解できる or わかりうる(when the subject is not the speaker).

知られる (passive) - it is being known

知られる is more likely "it is known."

もらえる (potential) I can receive it.

As an auxiliary verb, ～てもらえる is often used for "Someone will do something for me", or used as a request in interrogative sentences like ～てもらえますか？