the question(s) you are asking is unanswerable.
you have to adopt a methodology that suits your trading personality, and stick to it. there is no "right" timeframe. I personally look at a 5 minute, a 15 minute, and a 233 tick charts along with Market Profile (I use volume based
value areas and
POC not time based btw)...
but that's me.
charts are merely models of what the market is doing. there is no right and wrong timeframes, tickframes, volumeframes, etc. you don't even need to use a chart at all if you don't want. i've seen a trader trade merely using tick, tape, and pit noise. all models necessarily filter out information. you have to decide what is and isn't important in your methodology.
simply put... it depends.
there is no perfection in trading. even the best trader is frequently WRONG. that's cause market analysis is probabilistic. there is no determinism here. it's a chaotic dynamic feedback system. it's not a swiss watch.
the market necessarily adapts to what traders are doing, since it IS the sum total of all trades. what may work best NOW may not work as well 6 months from now, and almost certainly will not be as useful 10 years from now. there are many consistencies over time, but also many changes.
i'm not trying to get all mystical
it's far more important to have a solid business plan, solid risk management, solid discipline and a workable system with an edge, than to seek out optimum candles, etc.
the mere fact that one is trying to do the latter distracts from the real aspects of trading which are managing risk while applying one's edge.