Much more+dangerous Much more+ time-consuming Much more+ annoying Much more+ selective Much more + jovial Much more+ responsible It basically just depends on the suffix of the adjective and the number of syllables. There are certain endings that sound weird when attached to -er, such as the examples above. You wouldn’t say jovialer, selectiver, responsibler, time-consuminger, annoyinger, or dangerouser. You’d just initiate these expressions with “more”. The main reason why you’d use “more” is because these adjectives have more than one syllable and the suffix is not “y”. Words that don’t need “more” are nice (nicer), pretty (prettier), easy (easier), big(bigger), short (shorter)... The main reason why you’d use -er is because these adjectives have one syllable.

Yes these are all fine.

It’s fine the way it is.

“Trying to win in every dispute” would be better than “ Trying to get the advantage when you were having a dispute with them“