I don't know if you watch F3, but Schumachers race craft is excellent, the reason he was weak up until Spa was that he lacked qualifying pace and he's obviously improved in that area. He raced in two F4 championships in 2016 and only lost out marginally to two more experienced drivers who each concentrated on a single series.
Of course he needs to keep his form in F2 or where ever he moves next season, if he wants to be a serious contender for an F1 seat.
Palmer wasn't good enough for F1 and it goes to show that titles don't mean anything once a driver has reached F1. Perez and Palmer are perfect examples. Ask yourself, why is Perez racing in his 8th F1 season and Palmers ended after 1 and a half?
Perez showed enough talent in junior formulas that warranted the notion that he was a potential super star.
Lance Stroll is a pay driver or else Williams wouldn't have signed him, but the were desperate. He brought £80 million to the team. He was too inexperienced for F1 and could probably still do with another year in GP2. His pace in comparison to Massa was abysmal in qualifying and he couldn't even hold his own against him in the races either judging by the timing sheets. The positive about Stroll is that he knows how to keep his nose out of trouble and how to finish a race.
Maldonado was the crash kid from the day he entered F1 because he had plenty of crashes in lower formulas and continued to regularly crash in F1.
Think about your examples and how they performed or are performing in F1 in comparison to their team mates and you'll have the answer as to why some have a reputation that proceeds them.