Time to eat X.
X is ready to be eaten.
Can -koro/-goro be used as a general pattern by adding to masu-stem of the verb to produce meaning, that it is time to do this?
Time to kill X.
X is ready/better to be killed.
Time to listen to X.
X is ready/better to be listened.
If it would be a pattern, is it ok to use hiragana for this pattern or it is better with kanji like this?
Or both options (with kana or with kanji) are ok?
Here is a great answer on kanji vs kana for service grammar parts https://japanese.stackexchange.com/a/17388/34165