A general question about climbing

I'll ask this 3 different ways so I know I'm being clear.

1. Does difficulty in climbing out of Bronze 5 give you any indication of climbing out of Bronze 4?
2. How much does the tradeoff matter between carrying deadweight and finding more quality players?
3. How can I tell if what has been working for me now will be obsolete soon?

Hopefully that made my point. I'm worried, having found a reasonable strategy of using the same three champs in 2 roles, how quickly this won't work.