Metro North has good reverse commuting options, especially for those people who might live in the South Bronx and need to get work in like White Plains. There are many lower income people who might live in the Bronx and commute to jobs in Westchester County that pay very well. Having Melrose and Tremont are more important than you might think. If those stations didn't exist, then many of those people living near them would probably have to take a subway to a Bee Line bus or else a NYCMTA bus to a Bee Line bus(takes a painfully long time).
I'll give you a few: Merritt 7, Beacon Falls, Tenmile River, University Heights, Philpse Manor, Ludlow, Southport. Otisville is useless, but that is not really Metro-North.
I won't bother with the hiking stops since they take so little to maintain and they aren't commuter-oriented, so low ridership is acceptable. Tremont and Melrose, even though they have very low inbound ridership, they have a decent customer base who reverse commutes. Therefore, while they aren't important, Tremont and Melrose aren't useless either. I get that Merritt 7 probably has some people that get off there from Stamford, etc. but it doesn't need a 7 car high-level platform. A setup like the one they have on MBTA with a mini-high would be fine. Rowayton might as well just end weekend service, nobody gets on. Tenmile could become a hiking stop, Southport is close enough to both Green's Farms and Fairfield, Ludlow has low ridership, same with the Heights stations (especially University)