While I rather disliked the (admittedly impressive) VGA close-ups in MI 1 back then (too much detail, compared to the rest of the game and therefore misplaced somehow), the cover art for MI 1 & 2, which had quite realistic styles as well, made the games even more immersive to me, when I was a kid.
I’m not sure if it still would have done so in my current age, though. Also, I first played and enjoyed the games without having seen the cover art, because I first had pirated copies. By the way, the cinematic cover art was one of the reasons why I wanted to buy it later on.
However, up to now, I have no hope for cover art with such a style, since the trailer and the web site share the game’s art style. Nonetheless, it would have been awesome if Steve Purcell had done this job one more time.