Re: IDW Star Trek Ongoing...
Chekov Prime was ill-equipped to be security chief too (he was naive and more interested in scientific trivia than security protocols and he was always geting beaten up) but he did make a competent bridge tactical officer.
Chekov Prime is also a completely different character from the Abramsverse version and was also 25-30 years old when made security chief in the Prime timeline. Uhura would make a far more convincing security chief in the new universe.
"If I hadn't tried, the cost would have been my soul." - Admiral James T. Kirk, Star Trek III: The Search for Spock