The phrase "almost vital" is correct and usable in written English.
It can be used to describe something that is nearly essential or very important, but not quite at the level of being absolutely necessary.
Example: "While the new software is almost vital for our operations, we can still manage without it for a short period."
Alternatives: "nearly essential" or "practically crucial".
Sometimes the fiction is what takes me into the factual, the fiction lighting the inquisitive spark that makes further research almost vital.
His right-handed bat would seem almost vital for the Mets in 2013, but he is a free agent almost certainly looking for a lucrative two-year deal that is probably out of range for the still-frugal Mets.
As someone who has dealt with bipolar disorder, anger control issues and alcohol abuse, I have an almost vital need to trace the connections my brain makes.
I would love to intern more while I have this time of my studies, but I just can't afford it what's even more worrying is intern experience is almost vital for the jobs I want to get.
This is almost vital to your arena's foundation.
However, if you apply concealer, it is pretty (almost) vital that you apply foundation.
Discussing that low critical opinion in a 1942 essay, George Orwell considered Danny Deever as an example of Kipling "at his worst, and also his most vital... almost a shameful pleasure, like the taste for cheap sweets that some people secretly carry into middle life".
An odd idea when you consider that most of his potential electorate now lives in that sprawl, and seem to like it; and a dangerous one, once you acknowledge that sprawl is now the home of almost everything that is most vital and daring, if not most beautiful, in America.
I don't think they're his most vital work, but, as with almost anything Bearden produced, they are nice to look at and maybe more vital than I think.
"Winning the public-relations battle is almost as vital as military victory," said the Sunday Times.
Officer Norum said the medic told him that the woman had almost no vital signs.
