There are several wrong statements in this story but this is a fact.
The final recorded ping at 8:11 KL time exceeded many earlier estimates for its potential time in flight. How much fuel was really loaded and those loading it should be investigated.
Comparing the possible positions at each recorded ping (only the last has been released to my knowledge) would also be interesting. Don't know why they haven't released the others, but I can dream the plane didn't move between the last two pings so is known down, it has been spotted and Uncle Mao is en route to the rescue. Or, if it went far enough, Uncle Vlad might rescue them—he could use the PR.
Some have suspected a Malaysian coverup. The co-pilot turns out to be the son of a high ranking civil servant. Powerful fathers can run coverups. Early reports described him as "religious" and "a good muslim" contrasting his behavior inviting girls into his cockpit. While those labels may sound good for local Malaysian audiences they'd raise different issues here.
Getting to the final ping site, at least to the more interesting northern option (and who'd elaborately plan a slow suicide) means avoiding many radars. Either defenses there are much worse than presumed or the perps had the knowledge and skill to evade them. Determining what the perps could have known about those defenses and reverse engineering their possible routes may be enlightening. In the least it would be a good exercise for some bright military pilots.