UniFi equipment is fantastic. I actually manage some moderate-to-large deployments of UniFi equipment for marinas, and would not use anything else for those harsh environments. As fast as this tech updates, it’s not worth investing in the bigger vendors since replacing it every 2-3 years is possible with the cheaper UniFi equipment.
UniFi aboard is very popular. I actually use their access points on Aruna as well when the Peplink ones start misbehaving. Their management software and compatibility of their access points is very, very good. Everything connects fine and works very well.
The challenge is at the router side. Their products are built for normal land-based internet connections so they lack a lot of the features around cellular connections and optimizing things at that level. They could definitely handle multiple Starlink connections, but bonding and VPNs would be dealt with differently and likely not as gracefully.
You could use their access points, like I do, and Peplink for the router part. Or you could use UniFi’s router/dream machine/etc. “behind” the Peplink so you get all of the features of their router, and let the Peplink do the internet connections. Would use more power of course.