You could get rid of just about any of the TNG characters and it would not be that big of a deal.
Patrick, Brent, their agents and Paramount disagree with you.
"Generations" without the participation of Picard and/or Data
would not have been tenable. Those actors' fan mail piles outnumbered everyone else's.
More likely, we'd have probably gotten a series of telemovies instead: the Riker and Troi show. But Paramount wanted movies, not telemovies. (Similarly, there were actual plans for telemovies with Saavik and David, had Nimoy refused to return after ST II and had Shatner's movie career took off the way he envisaged at the time.)