The phrase "a far more engaging" is correct and usable in written English.
It can be used when comparing the level of engagement of two or more subjects, indicating that one is significantly more engaging than the other.
Example: "The sequel to the movie was a far more engaging experience than the original."
Alternatives: "much more captivating" or "significantly more interesting".
It's a far more engaging mix than it sounds.
I find Bilbo, the hero of the earlier book, a far more engaging character.
McEnroe and Agassi then took to the court for what turned out to be a far more engaging encounter.
But this time Tomas Maier presented a far more engaging and individual view of dressing than he has in the past.
Even at his most pedestrian or bombastic, Snyder makes a far more engaging film than Christopher Nolan (an executive producer of "Batman v Superman") ever did because Nolan presumes to know and to show, whereas Snyder wants to see.
But the five-seater is a far more engaging driver than the Prius V, accelerating with verve (thanks to a 54hp advantage in overall system horsepower) cornering ably despite weighing some 300lbs more than the V, and stopping without drama.
Peter Wanless, chief executive of the charity the NSPCC, called on the government to construct a process "far more engaging and involving of those with a direct interest in uncovering the truth about child abuse".
The acting and direction were perfectly pitched and paced and the result was a proper story, far more engaging than whatever Stephen Poliakoff might achieve over several hours.
Telling people what they will gain from a shift to a sustainable lifestyle is far more engaging and powerful than telling them what they might lose.
Jonathan's suspicions became aroused as the following story about the construction of a motorway through six villages would have been far more engaging as a front-pager.
It's a bit strange at first, but it's also far more engaging than a static page – I often find myself staring at the stream, simply so I can watch the next item to pop up (yes, I am easily amused).
